Community Pharmacy

COMMUNITY PHARMACY 2e SYMPTOMS, DIAGNOSIS AND TREATMENT Australian and New Zealand edition

Paul Rutter & David Newby


2012 201 2 Els Elsevi evier er Aus Austra tralia lia

© 201 2012 2 Els Elsevi evier er Aus Austra tralia lia


Paul Rutter BPharm, MRPharmS, PhD Principal Lecturer, School of Pharmacy, University of Wolverhampton, UK David Newby BPharm, PhD Associate Professor, Faculty of Health, University of Newcastle, Australia Original UK edition by Paul Rutter

Sydney Edinburgh London New York Philadelphia St Louis Toronto © 201 2012 2 Els Elsevi evier er Aus Austra tralia lia

Contents Preface Preface to the UK edition Introduction How to use this book Acknowledgements UK acknowledgements Useful websites

vii viii ix xiii xvi xvii xviii

1

Respiratory system

1

2

Ophthalmology

43

3

Otic conditions

65

4

Central nervous system

77

5

Women’s health

99

6

Gastroenterology

123

7

Dermatology

181

8

Musculoskeletal conditions

245

9

Paediatrics

267

10

Specific product requests

293

Answers to case study questions Abbreviations Glossary of terms Index

307 313 315 317



Preface Community pharmacy has evolved significantly over the last few decades. Although the role of pharmacists in delivering primary healthcare has been longstanding, the demand for self-care in the community has increased dramatically. In Australia it is estimated that over $4 billion is spent annually on self-care items, most of which are medicines. This contrasts with just over $8 billion spent annually on medicines subsidised on prescription by the government through the Pharmaceutical Benefits Scheme. A number of factors have influenced the trend towards greater self-care, including increased patient autonomy, better access to information about treatments and the availability of more effective non-prescription medicines. The latter has come about partly through the rescheduling of prescription medicines to non-prescription. Pharmacists in Australia and New Zealand are in a unique position in that the scheduling of medicines in these countries includes a special classification, Pharmacist Only (or Restricted in NZ), which falls between the Prescription Only and Pharmacy Only schedules, and requires involvement of the pharmacist in their sales. This contrasts with the UK, which only has Prescription Only and Pharmacy classifications, and the USA, where medicines are either Prescription Only or they can be sold in a range

of retail outlets. Drugs that fall into the Pharmacist Only category are those that, it has been decided, would benefit from the input of the pharmacist. This should be seen as a privilege, and not be taken for granted. It is important that pharmacists use this opportunity to demonstrate that the public gains by these additional restrictions. Some may argue that community pharmacy has clear conflicts of interest. On the one hand, as a healthcare professional, the health and safety of the patient are paramount. However, as a retailer, profitability and making sales are important. Community pharmacists make a significant amount of their income by selling things, in contrast to other healthcare professionals who are largely remunerated for their cognitive services. Therefore, it is important that, when assisting the public in making choices about purchasing medicines, pharmacists ensure their advice and guidance is based on the best available evidence to maximise the outcomes for the patient. It is hoped that this book will help pharmacists, both practising and in training, to diagnose and differentiate problems that are amenable to self-care, and then make choices of appropriate management that have evidence to support their efficacy.


David Newby

Introduction Community pharmacists are the most accessible healthcare professionals. No appointment is needed to consult a pharmacist and patients can receive free, unbiased advice almost anywhere. On a typical day a pharmacist practising in an ‘average’ community pharmacy can realistically expect to help between 5 and 15 patients who present with various symptoms for which they are seeking advice, reassurance, treatment or a combination of all three. Unlike most other healthcare professionals, community pharmacists do not normally have access to the patient’s medical record and thus have no idea about what the person’s problem is until a conversation is initiated. This presents the community pharmacist with a great challenge to correctly differentially diagnose the patient.

Communication skills For the most part pharmacists will be totally dependent on their ability to question patients in order to arrive at a differential diagnosis. This is in stark contrast to the GP and, to a lesser extent, the nurse, who can draw on physical examination and diagnostic tests to help them arrive at a diagnosis. Opportunities for pharmacists to perform a physical examination are limited by the lack of privacy within a pharmacy and also a lack of training in correct examination technique; diagnostic testing is never employed because of the costs (which would have to be passed on to the patient) and the invasive nature of most tests (e.g. blood taking for analysis). Having said this, a number of studies have shown that, in more than three-quarters of all cases, taking a patient history alone will result in the correct diagnosis. This figure rises slightly if a history is supplemented with a physical examination and yet further if laboratory investigations are also conducted. It is vital, therefore, that pharmacists possess excellent communication skills to ensure the correct information is obtained from the patient. This will be drawn from a combination of good questioning technique, listening actively to the patient and picking up on non-verbal cues. In addition to having skills in listening, the pharmacist must also be able to communicate information to the patient. While this is often done verbally, it is important that, where appropriate, written information is provided to back up any verbal instructions. Many of the websites provided at the end of each disease state and in the ‘Useful websites’ section of this book provide links to additional information to supplement counselling. Also,

all Pharmacist Only medicines in Australia are required to have a Consumer Medicines Information leaflet, as do some Pharmacy Only medicines. If appropriate, these should also be considered. Another good source of written materials is the Pharmacy Self Care fact sheets, available through the Pharmaceutical Societies in Australia and New Zealand (see www.psa.org.au and www.psnz.org.nz).

Approaches to differential diagnosis Try to avoid using acronyms Traditionally, the use of acronyms has been advocated to help pharmacists remember what questions to ask a patient. However, it is important that pharmacists do not rely solely on acronyms in trying to differentially diagnose a person’s presenting complaint; acronyms are rigid, inflexible and often inappropriate. Every patient is different and therefore it is unlikely that an acronym can be fully applied and, more importantly, using acronyms can mean that you miss vital information that could shape your course of action. Some of the more commonly used acronyms are discussed briefly below.

WWHAM This is the simplest acronym to remember but it is also the worst one to use. It gives the pharmacist very limited information from which to work and it is unlikely that a correct differential diagnosis will be made. If used at all, it should be with caution and it is probably only useful for counter assistants to use when a patient first presents, so that a general picture of the person’s presenting complaint can be established. Meaning of the letter W Who is the patient? W What are the symptoms? H How long have the complaint symptoms been present? A Action taken? M Medication being taken?


Attributes of the acronym Positive points Establishes presenting

Negative points Fails to consider general appearance of patient. No social/lifestyle factors taken into account; no family history sought; not specific or in-depth enough; no history of previous symptoms

x

Introduction

Other acronyms that have been suggested as being helpful for pharmacists in differential diagnosis are ENCORE, ASMETHOD and SIT DOWN SIR. Although these three acronyms are more comprehensive than WWHAM, they are still limited. No one acronym takes into consideration all of the factors that might impinge on the differential diagnosis. All fail to establish a full history from the patient in respect to lifestyle and social

E N C O R E

Meaning of the letter

Attributes of the acronym

Explore No medication Care Observe Refer Explain

Positive points ‘Observe’ section suggests taking into account the appearance of the patient – does he or she look very unwell? Negative points Sections on ‘No medication’ and ‘Refer’ add little to the differential diagnosis process. No social/lifestyle factors taken into account; no family history sought

A S M E T H O D



Age/appearance? Self or someone else? Medication? Extra medicines? Time persisting? History? Other symptoms? Danger symptoms?

Positive points Establishes the nature of the problem and if the patient has suffered from previous similar episodes Negative points Exact symptoms and severity not fully established. No social/lifestyle factors taken into account; no family history sought



S I T D O

Site or location? Intensity or severity? Type or nature? Duration? Onset?

Positive points Establishes the severity and nature of problem and if the patient has suffered from previous similar episodes

W N S I

With (other symptoms)? Annoyed or aggravated? Spread or radiation? Incidence or frequency pattern? Relieved by?

R

Negative points Fails to consider general appearance of patient. No social/lifestyle factors taken into account; no family history sought

factors or the relevance of a family history. They are very much designed to establish the nature and severity of the presenting complaint. This, in many instances, will be adequate but for intermittent conditions (e.g. irritable bowel syndrome, asthma, hayfever) they might well miss important information. Likewise, positive family history with certain conditions (e.g. psoriasis, eczema) provides useful clues in establishing a diagnosis. The Pharmaceutical Society of Australia has developed a protocol for non-pharmacist staff for both symptom-based requests and product-specific requests. The protocol is based around the words WHAT, STOP and GO: WHAT – what is the problem STOP – assess the situation GO – proceed if appropriate The acronyms WHAT and STOP stand for: Meaning of the letter W H A T

Who is the patient? How long have they had the symptoms? Actual symptoms – what are they? Treatment for this or any other conditions?

S T O P

Symptoms that should be referred Totally sure? Overuse or abuse? Pharmacist only or pharmacist preferred*

*Where the patient expresses a desire to speak to the pharmacist

If non-pharmacist staff encounter any of the STOP conditions they should refer to the pharmacist. This protocol is aimed at screening patients, and pharmacists are encouraged to use the guide to develop protocols in specific areas of the pharmacy.

Clinical decision making Whether we are conscious of it or not, most people will – at some level – use clinical decision making to arrive at a differential diagnosis. Diagnostic reasoning is a component of clinical decision making and involves recognition of cues and analysis of data. Very early in a clinical encounter, and based on limited information, a pharmacist will arrive at a small number of hypotheses. The pharmacist then sets about testing these hypotheses by asking the patient a series of questions. The answer to each question allows the pharmacist to narrow down the number of possible diagnoses either by eliminating particular conditions or confirming his or her suspicions of a particular condition. Once the questioning is over, the pharmacist should be in a position to differentially diagnose the patient’s condition.


Introduction

xi

● epidemiology states that tension headache is most

Key steps in the process 1. Formulating a diagnosis based on the patient and the initial presenting complaint Before any questions are asked of the patient you should think about the line of questioning you are going to take: ● What is the general appearance of the patient? Does

the person look well or unwell? Is the person you are about to talk to the patient or someone acting on the patient’s behalf? This will shape your thinking as to the severity of the problem. ● How old is the patient? This is very useful information. Epidemiological studies for a wide range of conditions and disease states have shown that certain age groups will suffer from certain problems. For example, it is very unlikely that a child who presents with cough will have chronic bronchitis but the probability of an elderly person having chronic bronchitis is much higher. ● What sex is the patient? As with age, sex can dramatically alter the chances of suffering from certain conditions. Migraines are five times more common in women than men, yet cluster headache is nine times more common in men than women. ● What is the presenting complaint? Some conditions are much more common than others. Therefore you could form an idea of what condition the patient is likely to be suffering from based on the laws of probability. For example, if a person presents with a headache then you should already know that the most common cause of headache is tension headache, followed by migraine and then cluster headache. Other causes of headache are rare but obviously need to be eliminated. Your line of questioning should try to confirm or refute the most likely causes of headache.

2. Asking questions The questions you ask the patient will be specific to that patient. After establishing who the person is, how sick he or she is and what the presenting complaint is, a number of targeted questions specific to that patient should be asked. The following scenario will illustrate this point: A 31-year-old female asks for advice about a headache she has. What are your initial thoughts? (1. Formulating a diagnosis based on the patient and the initial presenting complaint): ● the patient is present ● the patient is female and in her early thirties ● the patient looks and sounds OK

likely but females are more prone to migraine than males. What line of questioning do you take? (2. Asking questions.) Your main aim is to differentiate between tension and migraine headache:

Nature of the pain Tension headache usually produces a dull ache, as opposed to the throbbing nature of migraine pain: ● patient’s response: dull ache ● pharmacist’s thoughts: suggestive of tension

headache.

Location of the pain Tension headache is generally bilateral; migraine is often unilateral: ● patient’s response: all over ● pharmacist’s thoughts: suggestive of tension

headache.

Severity of pain Tension headache is not usually severe and disabling; migraine can be disabling: ● patient’s response: bothersome more than stopping

her doing things ● pharmacist’s thoughts: suggestive of tension

headache. The answers so far are indicative of tension headache. However, further specific questions relating to lifestyle and previous and family history should be asked. It would be expected that there was no family history of migraine and there is probably some trigger factor causing the headache, for example increased stress due to work or personal pressures. The patient might therefore have had similar headaches in the past. Finally, even though at this stage you are confident of your differential diagnosis you should still ask a couple of questions to rule out any sinister pathology. Obviously you are expecting the answers from these questions to be negative to support your differential diagnosis. Any questions that invoke the opposite response to that expected will require further investigation.

3. Confirming facts Before making a recommendation to the patient it is always helpful to try and recap the information elicited. This is especially important when you have had to ask a lot of questions. It is well known that short-term working memory is relatively small and that remembering all the pertinent facts is difficult. Summarising the information at this stage will not only help you formulate your final


xii

Introduction

diagnosis but will also allow the patient to add further information or to correct you on facts that you have failed to remember correctly. The way in which one goes about establishing what is wrong with the patient will vary from practitioner to practitioner. However, it is important that whatever method is adopted it must be sufficiently robust to be of benefit to the patient. Using a clinical decision-making approach to differential diagnosis allows you to build a fuller picture of the patient’s presenting complaint. It is both flexible and specific to each individual, unlike acronyms.

Product-based requests Many people will come into a pharmacy to purchase a specific product. Pharmacists should never assume that just because the patient has heard of, or used, the product before that they are adequately informed about the medicine. It is important that product-specific requests are treated with the same rigour as symptom-based requests. Pharmacists should establish whether use of the product is appropriate. Inappropriate use in this context is not related only to overuse or abuse, but also includes using the wrong product for the symptoms, or not using the product in the optimal way (e.g. using analgesics

intermittently when regular use for short periods of time is more appropriate to break the pain cycle). After establishing who the medicine is for, and whether they have used it before, it is important that questions about the complaint being treated are asked including the severity and duration, anything they have tried so far, and what other medical conditions and medicines they may take. Only after establishing that use is appropriate should the sale proceed.

Documentation It is important that pharmacists document their activities. Apart from the legal requirements for documentation, such as the recording of the sales of certain Pharmacist Only medicines, professional standards and the Competency Standards for Pharmacists all state the need to maintain adequate records. This includes documenting overuse or inappropriate use of medicines, treatment plans, required follow-up of patients and referrals or discussions with healthcare professionals. This may be done electronically using the patient records of the dispensing computing system or in paper form, such as pre-printed referral forms. The latter are available from some of the suppliers of pharmacy stationery.


How to use this book This book is divided into ten chapters. The first nine are systems based and structured in the format shown in Figure 1. The final chapter is product based and has a slightly different format. A list of abbreviations and a glossary are included at the end of the book.

doesn’t know where the kidneys are. However, this book is not intended to replace an anatomy text and the reader is referred to the list of further reading for anatomy texts.

Self-assessment questions Key features of each chapter At the beginning of each chapter a short section addressing basic anatomy and history taking specific to that body system is presented. A basic understanding of the anatomical location of major structures is useful when attempting to diagnose/exclude conditions from a patient’s presenting complaint. It would be almost impossible to know whether to treat or refer a patient who presented with symptoms suggestive of renal colic if one

1. Respiratory system 2. Ophthalmology 3. Otic conditions 4. Central nervous system 5. Women's health 6. Gastroenterology 7. Dermatology 8. Musculoskeletal conditions 9. Paediatrics 10. Specific product requests

Twenty multiple choice and at least two case study questions are presented at the end of each chapter. These are designed to test factual recall and applied knowledge. They start with simple traditional multiple choice questions in which the right answer has to be picked from a series of five possible answers, and work up to more complex, interrelated questions. The case studies challenge you with ‘real-life’ situations. All are drawn from practice and have been encountered by practising pharmacists, but have been modified

Background General overview of eye anatomy History taking Red eye Eyelid disorders Dry eye Self-assessment

Red eye Background Prevalence and epidemiology Aetiology Arriving at a differential diagnosis Clinical features of conjunctivitis Conditions to eliminate Primer for differential diagnosis Trigger points indicative of referral Evidence base for OTC medication Practical prescribing and product selection Hints and tips Further reading and websites

Fig. 1 Structure of this book. © 201 2012 2 Els Elsevi evier er Aus Austra tralia lia

xiv

How to use this book

for inclusion in the book. For all questions, a set of answers is provided at the end of the book to allow self-reflection.

Elements included under each condition The same structure has been adopted for every condition. This is intended to help the reader approach differential diagnosis from the position of clinical decision-making. To help summarise the information, tables and algorithms are included for many of the conditions.

Arriving at a differential diagnosis A table summarising the key questions that should be asked for each condition is included. The relevance (i.e. the rationale for asking the question) is given for each question. This will allow pharmacists to determine what questions to ask of every patient to enable a differential diagnosis. For some conditions, such as those that affect the eye and some skin conditions, it will be possible for the pharmacist to have a look at the affected area. We would

encourage pharmacists to examine these conditions if possible—to assist in this, photographs demonstrating standard presentations of these complaints have been included in those chapters relating to these types of conditions. However, it is important to note that patients may not present with ‘classical’ signs, and careful questioning is usually required to help reach a differential diagnosis.

Primer for differential diagnosis A ‘primer for differential diagnosis’ is available for a number of the conditions covered. This algorithmic approach to differential diagnosis is geared towards nearly or recently qualified pharmacists. This feature is not intended to be solely relied upon in making a differential diagnosis but to act as an aide memoire. It is anticipated that the primers will be used in conjunction with the text, thus allowing a broader understanding of the differential diagnosis of the condition being considered.

Trigger points indicative of referral A summary box of trigger factors when it would be prudent to refer the patient to a medical practitioner is presented for each condition.

Table 1. ADEC pregnancy categories ADEC category

Definition

A

Drugs which have been taken by a large number of pregnant women and women of childbearing age without any proven increase in the frequency of malformations or other direct or indirect harmful effects on the fetus having been observed

B1

Drugs that have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have not shown evidence of an increased occurrence of fetal damage

B2

Drugs that have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals are inadequate or may be lacking, but available data show no evidence of an increased occurrence of fetal damage

B3

Drugs that have been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human fetus having been observed. Studies in animals have shown evidence of an increased occurrence of fetal damage, the significance of which is considered uncertain in humans

C

Drugs that, owing to their pharmacological effects, have caused or may be suspected of causing harmful effects on the human fetus or neonate without causing malformations. These effects may be reversible

D

Drugs that have caused, are suspected to have caused or may be expected to cause an increased incidence of human fetal malformations or irreversible damage. These drugs may also have adverse pharmacological effects

X

Drugs that have such a high risk of causing permanent damage to the fetus that they should not be used in pregnancy or when there is a possibility of pregnancy © 201 2012 2 Els Elsevi evier er Aus Austra tralia lia

How to use this book

Evidence-based non-prescription medicines and practical prescribing and product selection

xv

Hints and tips boxes

These two sections present the reader, first, with an evaluation of the current literature on whether a nonprescription medicine works and, second, with a quick reference to the dose of the medicine and when it cannot be prescribed. This does not replace textbooks such as Stockley’s drug interactions or Briggs’ Drugs in pregnancy and lactation, but it does allow the user to find basic data in one text without having to reach for three or four other texts to answer simple questions. The pregnancy recommendations in this book are based largely on those of the Australian Drug Evaluation Committee’s (ADEC) Pregnancy Categories (Table 1). In some instances respected evidence-based texts, such as the Australian Medicines Handbook, have taken a more pragmatic approach and have suggested limited use in pregnancy may be appropriate despite not having an ADEC category of A. In these instances this is noted in the summary tables. However, given that pharmacists should only be managing minor, self-limiting conditions, it is prudent that no medicines are recommended in the first trimester, unless they carry an ADEC category of A.

A summary box of useful information is provided near the end of each condition. This contains information that does not fall readily into any of the other sections but is none the less useful. For example, some of the hints and tips boxes give advice on how to administer eye drops, suppositories and other forms of medicines that are not taken via the oral route.

References, further reading and web sites To supplement the text, at the end of each condition a list of selected references and reading is provided for those who wish to seek further information on the subject. Web sites are also provided, as many people now have internet access. All the sites have been checked and were active and relevant at the time of writing (January 2011). Finally, all information presented in the book is accurate and factual as far as the authors are aware. It is acknowledged that guidelines change, products become discontinued and new information becomes available over the lifetime of a book. Therefore, if any information in the book is not current or valid, the authors would be grateful of any feedback, positive or negative, to ensure that the next edition is as up-to-date as possible.


Chapter

4

Central nervous system In this chapter Background 77 General overview of CNS anatomy 77 History taking 77

Headache 77 Insomnia 86 Self-assessment questions

Background

92

Headache

The number of patient requests for advice and/or products to treat headache and insomnia makes up a smaller proportion of a pharmacist’s workload than other conditions such as coughs and colds – yet sales for analgesics and hypnotics are extremely high. The vast majority of patients will present with benign and non-serious conditions and in only very few cases will sinister pathology be responsible.

Background Headache is not a disease state or a condition but rather a symptom, of which there are many causes. Headache can be the major presenting complaint, for example in migraine, tension and cluster headache, or one of many symptoms, for example in an upper respiratory tract infection.

Headache classification

General overview of CNS anatomy The central nervous system (CNS) comprises the brain and spinal cord. Its major function is to process and integrate information arriving from sensory pathways and communicate an appropriate response back via afferent pathways. CNS anatomy is complex and beyond the scope of this book. The reader is referred to any good anatomical text for a comprehensive description of CNS anatomy.

History taking A differential diagnosis for all CNS conditions will be made solely from questions asked of the patient. It is especially important that a social and workrelated history is sought alongside questions asking about the patient’s presenting symptoms because pressure and stress are implicated in the cause of CNS conditions.

If the pharmacist is to advise on appropriate treatment and referral then it is essential to make an accurate diagnosis. However, with so many disorders having headache as a symptom, pharmacists should endeavour to follow an agreed classification system. The 2nd edition of the International Headache Society (IHS) classification is now almost universally accepted (Table 4.1). The system first distinguishes between primary and secondary headache disorders. This is useful to the community pharmacist, as any secondary headache disorder is symptomatic of an underlying cause and would normally require referral. In the IHS system, primary headaches are classified on symptom profiles, relying on careful questioning coupled with epidemiological data on what the distribution of a particular headache disorder has within the population.

Prevalence and epidemiology The exact prevalence of headache is not precisely known. However, virtually everyone will have suffered from a headache at some time; it is probably the most common


78


Table 4.1 IHS Classification of headache Primary headache disorders

1. Migraine, including: 1.1 Migraine without aura 1.2 Migraine with aura 2. Tension-type headache, including: 2.1 Infrequent episodic tension-type headache 2.2 Frequent episodic tension-type headache 2.3 Chronic tension-type headache

Secondary headache disorders

5. Headache attributed to head and/or neck trauma, including: 5.2 Chronic post-traumatic headache 6. Headache attributed to cranial or cervical vascular disorder, including: 6.2.2 Headache attributed to subarachnoid 6.4.1 Headache attributed to giant cell arteritis 7. Headache attributed to non-vascular intracranial disorder, including: 7.1.1 Headache attributed to idiopathic intracranial hypertension 7.4 Headache attributed to intracranial neoplasm 8. Headache attributed to a substance or its withdrawal, including: 8.1.3 Carbon monoxide-induced headache 8.1.4 Alcohol-induced headache

Neuralgias and other headaches

13. Cranial neuralgias, central and primary pain and other headaches including: 13.1 Trigeminal neuralgia

3. Cluster headache and other trigemina autonomic cephalalgias, including: 3.1 Cluster headache 4. Other primary headaches

8.2 Medication-overuse headache 8.2.1 Ergotamine-overuse headache 8.2.2 Triptan-overuse headache 8.2.3 Analgesic-overuse headache 9. Headache attributed to infection, including: 9.1 Headache attributed to intracranial infection haemorrhage 10. Headache attributed to disorder of homeostasis 11. Headache or facial pain, attributed to disorder of cranium, neck, eyes, ears, nose, sinuses, teeth, mouth or other facial or cranial structures including: 11.2.1 Cervicogenic headache 11.3.1 Headache attributed to acute glaucoma 12. Headache attributed to psychiatric disorder 14. Other headache, cranial neuralgia, central or facial primary facial pain

Source: adapted by the British Association of Headache (BASH) from the International Headache Society Classification Subcommittee, The International Classification of Headache Disorders, 2nd ed. Cephalalgia 2004, Blackwell Publishing, with permission

pain syndrome experienced by humans. A study by Heywood and others (1998) involving 1717 individuals in Melbourne, Australia, found 87% reported at least one headache in the previous year. They also found that more than 1 in 10 had sought advice from a pharmacist about their headache. Tension headache has been reported to affect between 40 and 90% of people in Western countries at some time in their life. Migraine affects approximately 15% of women, in whom it is three times more common than in men. Prevalence peaks between 30 to 40 years of age. Conversely, cluster headache which is also more prevalent in the 30 to 40 year-old age group, is five to six times more prevalent in men.

Aetiology Considering headache affects almost everyone, the mechanisms that bring about headache are still poorly

understood. Pain control systems modulate headaches of all types, independent of the cause. However, the exact aetiology of tension headache and migraine are still to be fully elucidated. Tension headache is commonly referred to as muscle contraction headache, as electromyography has shown pericranial muscle contraction, which is often exacerbated by stress. However, similar muscle contraction is noted in migraine sufferers and this theory has now fallen out of favour. Consequently, no current theory for tension headache is unanimously endorsed but recent studies suggest a neurobiological basis. Traditionally, migraine was thought to be a result of abnormal dilation of cerebral blood vessels but this vascular theory cannot explain all migraine symptoms. The use of 5 HT1 agonists to reduce and stop migraine attacks suggests some neurochemical pathophysiology. Migraine is therefore probably a combination of vascular and neurochemical changes – the neurovascular hypothesis.


Headache Migraine also appears to have a genetic component with about 70% of patients having a first-degree relative with a history of migraine.

Arriving at a differential diagnosis Given that headache is extremely common, and most patients will self-medicate, any patient requesting advice should ideally be seen by the pharmacist, as it is likely that the headache has either not responded to nonprescription medicine or is troublesome enough for the patient to seek advice. Arrival at an accurate diagnosis will rely on careful questioning; therefore, a number of headache-specific questions should be asked (Table 4.2). In addition to these symptom-specific questions, the pharmacist should also enquire about the person’s social history because social factors – mainly stress – play a significant role in headache. Ask about the person’s work and family status to determine if the person is suffering from greater levels of stress than normal. Although careful questioning is important, many patients who

79

present with headaches can be defensive, especially if they feel they are undergoing an ‘inquisition’. Therefore, pharmacists must establish a report with the patient, while carefully explaining why the information will help with them assisting the patient.

Clinical features of headache In a community pharmacy the overwhelming majority of patients (80–90%) will present with tension headache. A further 10% will have migraine. Very few will have other primary headache disorders and fewer still will have a secondary headache disorder. This part of the text therefore concentrates on migraine, tension and cluster headaches.

Tension-type headache Tension-type headaches can be classed as either episodic or chronic. Episodic tension-type headache can be further subdivided into infrequent and frequent forms. Most

Table 4.2 Specific questions to ask the patient: Headache Question

Relevance

Onset of headache

● In early childhood or a young adult, primary headache is most likely. After 50 years of age the

likelihood of a secondary cause is much greater ● Headache and fever at the same time imply an infectious cause ● Headache that follows head trauma might indicate post-concussive headache or intracranial

pathology Frequency and timing

● Headache associated with the menstrual cycle or certain times, e.g. weekend or holidays,

suggests migraine ● Headaches that occur in clusters at the same time of day/night suggest cluster headache ● Headaches that occur on most days with the same pattern suggest tension headache

Location of pain (see Fig 4.1)

● Cluster headache is nearly always unilateral in frontal, ocular or temporal areas ● Migraine headache is unilateral in 70% of patients but can change from side to side from attack

to attack ● Tension headache is often bilateral, either in frontal or occipital areas, and described as a tight

band ● Very localised pain suggests an organic cause

Severity of pain

● Pain is a subjective personal experience and there are therefore no objective measures. Using a

● ● ● ●

numeric pain intensity scale should allow you to assess the level of pain the person is experiencing: 0 represents no pain and 10 the worst pain possible Dull and band-like suggests tension headache Severe to intense ache or throbbing suggests haemorrhage or aneurysm Piercing, boring, searing eye pain suggests cluster headache Moderate to severe throbbing pain that often starts as dull ache suggests migraine

Triggers

● Pain that worsens on exertion, coughing and bending suggests a tumour ● Food (in 10% of sufferers), menstruation and relaxation after stress are indicative of migraine ● Lying down makes cluster headache worse

Attack duration

● Typically migraine attacks last between a few hours and 3 days ● Tension headaches last between a few hours and several days, e.g. a week or more ● Cluster headache will only normally last 2 to 3 h © 201 2012 2 Els Elsevi evier er Aus Austra tralia lia

4

80

Central nervous system severely affect the patient’s quality of life and should not be managed by the community pharmacist. Tension or migraine

Migraine Frontal

Cluster, glaucoma, sinusitis

Orbital

Subarachnoid tension, haemorrhage Occipital

There are an estimated 2 million migraine sufferers in Australia, and the cost of migraine has been put at over $1 billion per annum (Parry 1992). The peak onset for a person to have their first attack is often in adolescence or as a young adult. Migraines are rare over the age of 50 and anyone in this age group presenting for the first time with migraine-like symptoms should be referred to the GP to eliminate secondary causes of headache. If this is not their first attack they will normally have a history of recurrent and episodic attacks of headache. Attacks last anything between a few hours and up to 3 days. The average length of an attack is 24 hours. The IHS classification recognises several subtypes of migraine. However, the major subtypes are migraine with aura (classical migraine) and migraine without aura (common migraine). A migraine attack can be divided into three phases: ● Phase one: premonitory phase (prodrome phase),

Migraine, temporal arteritis

Temporal

Fig. 4.1 Location of pain in headache.

patients will present to the pharmacist with the infrequent episodic form. Headaches last from 30 minutes to up to 7 days in duration and often the patient will have a history of recent headaches. They might have tried non-prescription medicine without complete symptom resolution or say that the headaches are becoming more frequent. Pain is bifrontal or bioccipital, generalised and non-throbbing (Figure 4.1). The patient might describe the pain as tightness or a weight pressing down on their head. The pain is gradual in onset and tends to worsen progressively through the day. Pain is normally mild to moderate and not aggravated by movement, although it is often worse under pressure or stress. Nausea and vomiting are not associated with tensiontype headache and it rarely causes photo- or phonophobia. Overall, the headache has only a limited impact on the individual. Patients who have frequent episodic tension-type headaches suffer more frequent headaches that last longer and over time these can develop into chronic tension-type headache. These headaches occur for more than 15 days per month, and might occur daily and last for at least 3 months. These types of headaches can

which can occur hours or possibly days before the headache. The patient may complain of a change in mood or notice a change in behaviour. Feelings of well-being, yawning, poor concentration and food cravings have been reported. These prodromal features are highly individual but are relatively consistent to each patient. Identification of ‘triggers’ is sometimes possible if a patient keeps a diary (Table 4.3). ● Phase two: headache with or without aura. ● Phase three: as the headache subsides the patient may feel lethargic, tired and drained before recovery, which may take several hours and is termed the resolution phase.

Headache with aura (classic migraine) This accounts for less than 25% of migraine cases. The aura, which are fully reversible, develops over 5 to 20 minutes and can last for up to 1 hour. It can either be visual or neurological. Visual auras can take many guises, such as scotomas (blind spots), fortification spectra (zig-zag lines) or flashing and flickering lights. Neurological auras (pins and needles) typically start in the hand, migrating up the arm before jumping to the face and lips. Within 60 minutes of the aura ending the headache usually occurs. Pain is unilateral, throbbing and moderate to severe. Sometimes the pain becomes more generalised and diffuse. Physical activity and movement tends to intensify the pain. Nausea affects almost all patients but less than a third will vomit. Photophobia and phonophobia often make patients seek a dark quiet room to relieve their symptoms. The patient might also


Headache

81

Table 4.3 Triggers and strategies to reduce migraine attacks Trigger

Strategy

Stress

● ● ● ●

Diet – any food could be a potential trigger but foods implicated include: Cheese Citrus fruit Chocolate

● Maintain a food diary. If an attack occurs within 6 hours of food ingestion and is

Maintain regular sleep pattern Take regular exercise Modify work environment Relaxation techniques (e.g. yoga) reproducible it is likely that it is a trigger for migraine

● Eat regularly and do not skip meals ● Note: detecting triggers is complicated because they appear to be cumulative jointly

contributing to a ‘threshold’ above which attacks are initiated

suffer from fatigue, find concentrating difficult and be irritable.

headache require referral, as OTC management is very unlikely to be effective.

Headache without aura (common migraine)

Rhinosinusitis

The remaining 75% of sufferers do not experience an aura but do suffer from all other symptoms as described above.

The pain tends to be relatively localised, usually orbital, unilateral and dull. A course of decongestants could be tried but if treatment failure occurs referral to the GP for possible antibiotic therapy would be needed. For further information on rhinosinusitis, see Chapter 1 page 13.

Cluster headache Cluster headache is predominantly a condition that affects men over the age of 30 years. Typically the headache occurs at the same time each day with abrupt onset and lasts between 10 minutes and 3 hours, with 50% of patients experiencing night-time symptoms. Patients are woken 2 to 3 hours after falling asleep with steady intense unilateral orbital boring pain, often described as being poked in the eye with a red-hot poker. Additionally, conjunctivitis and nasal congestion (which laterally becomes watery) are experienced on the same side of the head as the headache. The condition is characterised by periods of acute attacks, typically lasting a number of weeks to a few months with sufferers experiencing between one and three attacks per day. This is then followed by periods of remission, which can last months or years. During acute phases, alcohol can trigger an attack. Nausea is usually absent and a family history uncommon. The key differences between the three conditions are shown in Table 4.4.

Conditions to eliminate All suspected secondary causes of headache except sinusitis and alcohol-induced (‘hangover’) need to be referred. In addition, patients suffering from cluster

Eye strain Patients who perform prolonged periods of close work, for example people who look at computer screens for extended periods, can suffer from frontal aching headache. In the first instance, patients should be referred to an optometrist for a routine eye check.

Medication overuse headache Patients with long-standing symptoms of headache who medicate regularly, can develop medication overuse headache (MOH). The exact mechanism of MOH is poorly understood but may include genetic factors and/or changes in serotonin receptors that promote pain. Patients with migraine and tension headaches seem to be at greatest risk. The result is a cycle where patients take more and more painkillers that are stronger and stronger in order to control the pain. Patients will experience daily or near daily headaches that are described as dull and nagging. Obviously in these cases a medication history is essential and should prompt the pharmacist to refer the patient to the GP. Treatment is to stop all analgesia for a number of weeks and requires careful planning. However, like many things prevention is better than cure, and therefore pharmacists should intervene as soon as

2012 201 2 Els Elsevi evier er Aus Austra tralia lia

4

82


Table 4.4 Difference in symptom presentation for primary headaches Severity (pain score from 0–10)*

Precipitating factors

Who is affected

2–5

Stress due to changes in work or home environment

All age groups and both sexes equally affected

Usually unilateral

4–7

Food (in 10% of sufferers) and family history

Three times more common in women. Rare in children

Unilateral, often behind the eye or temples

>7

Alcohol

Three to five times more common in men

Duration

Timing and nature

Location

Tensiontype

Can last days

Symptoms worsen as day progresses. Non-throbbing pain

Bilateral and most often at back of head

Migraine

Average attack lasts 24 hours

Associated with menstrual cycle and weekends Throbbing pain and nausea. Dislike of bright lights and loud noise

Cluster

1–3 hours

Attacks occur at same time of day Intense boring pain

*These are rough guides set by the authors and are not evidence-based

possible if they think someone is over using medicines for headaches.

unlikely that a patient would present in the pharmacy with such symptoms but if one did then immediate referral is needed.

Glaucoma Patients experience a frontal/orbital headache with pain in the eye. Sometimes, but not often, the eye appears red and is painful. Vision is blurred and the cornea can look cloudy. In addition, the patient might notice haloes around the vision. For further information on glaucoma see Chapter 2 page 47.

Meningitis Severe generalised headache associated with fever, an obviously ill patient, neck stiffness, a positive Kernig’s sign (pain behind both knees when extended) and latterly a purpuric rash are classically associated with meningitis. However, meningitis is notoriously difficult to diagnose early and any child who has difficulty in placing the chin on the chest, looks and feels unwell, has a headache and a temperature above 38.9°C should be referred urgently to accident and emergency as the patient can decline rapidly and has a case fatality rate of 5–10%, higher if they develop sepsis.

Subarachnoid haemorrhage The patient will experience very intense and severe pain, located in the occipital region. Nausea and vomiting are often present and a decreased level of consciousness is prominent. Patients often describe the headache as the worst headache they have ever had. It is extremely

Temporal arteritis The temporal arteries that run vertically up the side of the head, just in front of the ear, can become inflamed. When this happens, they are tender to touch and might be visibly thickened. Unilateral pain is experienced and the person generally feels unwell with fever, myalgia and general malaise. Scalp tenderness is also possible, especially when combing the hair. It is most commonly seen in the elderly, especially women. Prompt treatment with oral corticosteroids is required because the retinal artery can become compromised, leading to blindness. Urgent referral is needed.

Conditions causing raised intracranial pressure Space-occupying lesions (brain tumour, haematoma and abscess) can give rise to varied headache symptoms, ranging from severe chronic pain to intermittent moderate pain. Pain can be localised or diffuse and tends to be more severe in the morning, with a gradual improvement over the next few hours. Coughing, sneezing, bending and lying down can worsen the pain. Nausea and vomiting are common. After a prolonged period of time neurological symptoms start to become evident, such as drowsiness, confusion, lack of concentration, difficulty with speech and paraesthesia.


83

Headache Any patient with a recent history (last 2 to 3 months) of head trauma, headache of longstanding duration or insidious worsening of symptoms, especially decreased consciousness and vomiting, must be referred for fuller evaluation.

always unilateral. It is three times more common in women than men.

Depression Depression often presents with tension-like headaches. Check for loss of appetite, weight loss, decreased libido, sleep disturbances and constipation. If the patient exhibits these characteristics then referral to the GP would be necessary to determine if the patient is suffering from depression. Recent changes to the patient’s social circumstances, for example loss of job, might also support your differential diagnosis. Figure 4.2 will help in the differentiation of serious and non-serious causes of headache.

Trigeminal neuralgia Pain follows the course of either the second (maxillary – supplying the cheeks) or third (mandibular – supplying the chin, lower lip and lower cheek) division of the nerve leading to pain experienced in the cheek, jaws, lips or gums. Pain is short-lived, usually lasting only a couple of minutes, but is severe and lancing and is almost

4

Patient presents with headache No > 50 years New, severe headache

Signs of infection > 12 years but < 50 years

No

Yes Refer ❷ Sinister pathology? Yes

No

Unilateral pain Yes

No Cluster

❶

Age

No

Orbital pain and tearing

Throbbing pain

No

No

Temples tender

Nausea and /or vomiting

Treat

No

Worse when stressed Yes

Nausea and/or vomiting

Yes

Yes

Pain dull and band-like Yes

Yes Refer

Refer

< 12 years

Yes

Tension headache

Yes

Temporal arteritis

Refer ❸ Sinister pathology?

Family history of migraine No

Yes

Pain worse in morning

No

Yes Refer Sinister pathology?

Migraine

No

Yes

Pain lasts < 3 days

Fig. 4.2 Primer for differential diagnosis of headache.

❶

Age Caution should be exercised in children who present with headache. Although the majority of headaches will not have an organic cause, children under 12 are probably best referred if they show no signs of a systemic infection (e.g. fever, malaise).

❷ Referral for suspected sinister pathology With increasing age it is more likely that a sinister cause of headache is responsible for the symptoms, especially if the patient

has not experienced similar headache symptoms before. Mass lesions (tumours and haematoma) and temporal arteritis should be considered.

❸ Referral for suspected sinister pathology Nausea and vomiting in the absence of migraine-like symptoms should be treated seriously. Mass lesions and subarachnoid haemorrhage need to be eliminated.


84


TRIGGER POINTS indicative of referral: Headache ● Headache unresponsive to adequate doses of

analgesics ● Headache in children under 12 years with stiff

neck or skin rash ● Headache occurs after recent (1 to 3 months)

trauma injury ● Headache that has lasted for more than 2 weeks ● Nausea and/or vomiting in the absence of ● ● ● ● ●

migraine symptoms Neurological symptoms, if migraine excluded, especially change in consciousness New or severe headache in patients over 50 years Progressive worsening of headache symptoms over time Symptoms indicative of cluster headache Very sudden and/or severe onset of headache

the additional benefit appears modest at best (for more information see lower back pain in Chapter 8, page 246. It should also be noted that long-term trials are lacking and therefore the potential for the caffeine to cause a withdrawal headache, resulting in a cycle of increased analgesic use as seen with older pain relievers such as APC powders, has not been fully investigated.

Metoclopramide and paracetamol The non-prescription preparations contain paracetamol 50 mg and metoclopramide 5 mg per tablet. Although there is limited data on the efficacy of the combination product, several evidence-based guidelines, including the Therapeutic Guidelines and the NPS, advocate the combination of paracetamol and metoclopramide in the treatment of mild/moderate migraine where nausea/vomiting are present.

Prochlorperazine

Evidence base for non-prescription medicines Simple analgesia (paracetamol, aspirin and ibuprofen) has shown clinical benefit in relieving some migraine attacks and should be taken as early as possible. Approximately 60% of patients can expect a reduction in the severity of pain from moderate/severe to mild/none 2 hours after treatment but only a quarter of patients will be pain-free within 2 hours. Because migraine is associated with gastric stasis standard OTC doses might be inadequate to relieve migraine symptoms. Only one product, paracetamol plus metoclopramide, is specifically marketed OTC to aid relief from pain and nausea associated with migraine. Prochlorperazine in packs of 10 or less tablets is approved for OTC use in the treatment of nausea associated with migraine. A systematic review investigating comparative efficacy of simple analgesics for episodic tension-type headache concluded that all simple analgesics had similar efficacy (measured as >50% pain relief) (Verhagen et al 2006). However, the authors did suggest that ibuprofen might be more effective than paracetamol. Combinations of simple analgesics with codeine have been promoted for ‘strong pain’. However, there is doubt whether the amount of codeine in these preparations is sufficient to provide any additional pain relief. Further, there is growing evidence of problems with the over-use of these products resulting from dependence on the codeine components (Frei et al 2010). In response to the ongoing concerns about the over-use of codeine-containing products, all non-prescription analgesic products containing codeine were rescheduled in Australia and New Zealand in 2010 to require their sale only with the involvement of the pharmacist. Combinations of paracetamol and caffeine are also promoted for strong pain relief. However,

Prochlorperazine given parenterally has been shown in trials to be effective in reducing pain in migraine headaches when used without any analgesics (Coppola et al 1995). However, there is limited evidence of the efficacy of oral prochlorperazine in migraine headaches. Despite this, the Therapeutic Guidelines recommend the addition of prochlorperazine to simple analgesics if nausea is a problem in patients with a migraine.

Summary Simple analgesics are suitable for tension headaches and for some patients with migraines. There is insufficient evidence to support the claim that non-prescription combination analgesics containing low doses of codeine are stronger than simple analgesics alone, and they are likely to cause more side-effects. From the limited trial data reviewed it appears that paracetamol plus metoclopramide, or the addition of prochlorperazine to simple analgesics such as paracetamol or ibuprofen, may be useful in patients with mild to moderate migraine who suffer nausea/vomiting as part of their migraine attack. However, if nausea or vomiting were a prominent feature of a migraine attack, referral to a doctor would be required as rectal or parenteral routes for administering metoclopramide or prochlorperazine are required.

Practical prescribing and product selection Prescribing information relating to specific products used to treat migraine in the section ‘Evidence base for nonprescription medicines’ is discussed and summarised in Table 4.5, and useful tips relating to medication overuse headaches are given in Hints and Tips Box 4.1. Prescribing information relating to simple analgesics used for episodic tension headaches can be found in Chapter 8 under acute low back pain (page 246) and in Table 8.2.


Headache

85

Table 4.5 Practical prescribing: Summary of medicines for migraine Drug interactions of note

Patients in whom care should be exercised

Medicine

Use in children

Likely side-effects

Pregnancy

Paracetamol and metoclopramide

>12 years

Sedation; occasional dystonic reactions

Increased sedation with alcohol, opioid analgesics, anxiolytics, hypnotics and antidepressants

Young adults, particularly young women

Category A, but manufacturer warns against use

Prochlorperazine

>2 years; >12 years for buccal preparation

Sedation, dry mouth, possible Parkinsonlike symptoms

Drugs that prolong QT interval, levodopa

Very young and elderly

Category C; avoid

HINTS AND TIPS BOX 4.1: MIGRAINE Simple analgesia

Recommend a soluble formulation to maximise the absorption of analgesic before it is inhibited by gastric stasis, and instruct to patient to take the dose as soon as possible when the symptoms start

Codeine-containing preparations

Doses of codeine of greater than 30 mg are generally needed to provide any additional analgesic effect over and above that from simple analgesics alone. Further, in migraine codeine can worsen nausea and vomiting. Therefore, codeine-containing analgesics are best avoided.

Prevention of migraine

Patients should be encouraged to identify and avoid triggers such as certain foods, stress, and overworking. Relaxation therapy and yoga may help some patients

Metoclopramide plus paracetamol The non-prescription products are approved for use in adults, and children over 12 years of age. The recommended dose for adults is one or two tablets/capsules to start, then one or two tablets/capsules every 4 hours as required, with a maximum of six tablets in 24 hours. The dose for adolescents aged 12 to 17 years is one tablet to start and then one tablet every 4 hours as required, with a maximum of three tablets per day. At therapeutic doses metoclopramide and paracetamol are generally well tolerated. However, up to 10% of people may suffer drowsiness and fatigue due to the metoclopramide. A rare side-effect of metoclopramide is dystonic reactions. These are more common in younger people ( 3 weeks

Signs of anxiety or depression

No Treat

❷

Yes

❸

Yes

Altered sleep pattern

Drug induced

❸

Yes

Yes Contact GP to review the management of the patient

No Underlying condition

Stress related No

Treat

Refer

No

No Treat

Yes

Yes

No

Poor sleep hygiene

Refer

No Refer

No

Yes

Drug induced

Fig. 4.4 Primer for differential diagnosis of insomnia.

❶ No cases of insomnia lasting longer than 3 weeks should be treated with non-prescription medicine. If a previously undiagnosed medical condition is suspected, most often anxiety or depression, or if insomnia has been possibly caused by the patient’s preexisting condition/medicines, then the GP should be consulted and treatment options discussed/suggested.

behaviour and practice that affects sleep should be tackled (Table 4.8).

❷ Patients should not take antihistamines for more than 7 to 10 continuous days as tolerance to their effect can develop. ❸ In the first instance, strategies to manage the patient’s insomnia should be suggested rather than issuing medicines.

Table 4.8 Steps to good sleep hygiene ● Maintain a routine, with a regular bedtime and

Medicines

wakening time

The sedating antihistamines diphenhydramine and doxylamine are the mainstay of pharmacological treatment.

Diphenhydramine At doses of 50 mg diphenhydramine has been shown to be superior to placebo in inducing sleep, and as effective as 60 mg of sodium pentobarbitone (Rickels et al 1983; Teutsch et al 1975). Doses higher than 50 mg diphenhydramine do not produce statistically superior clinical effects and night-time doses should therefore not exceed this amount.

● Food snacks, alcoholic and caffeine-containing drinks

should be avoided Avoid sleeping in very warm rooms Daytime and not evening exercise No daytime naps No sleeping in to catch up on sleep No strenuous mental activity at bedtime (e.g. doing a crossword in bed) ● No watching television in bed ● Solve problems before retiring ● If unable to get to sleep, get up and do something ● ● ● ● ●

Doxylamine Doxylamine has been studied in a few small trials and has been shown to be superior to placebo, and compared favourably with secbutobarbitone (Rickels et al 1984; © 201 2012 2 Els Elsevi evier er Aus Austra tralia lia

4

90


Sjoqvist & Lasagna 1967). Like diphenhydramine, doxylamine has a flat dose-response with a 25 mg dose being similar to 50 mg. Although doxylamine and diphenhydramine have not been compared head-to-head, the shorter half-life of diphenhydramine may give it an advantage.

Summary Of the two sedating antihistamines, diphenhydramine has a shorter half-life and therefore may be the treatment of choice. However, it should be noted that the Australian Medicines Handbook and the National Prescribing Service (NPS) caution against the use of sedating antihistamines to treat sleep disorders due to the limited evidence of efficacy, the rapid development of tolerance, and their potential to produce adverse effects.

Complementary therapies Herbal remedies containing hops, German chamomile, skullcap, wild lettuce, passiflora and valerian are available and widely used. A US study found 4.5% of people had used a complementary therapy to treat insomnia (Pearson et al 2006). However, there is little evidence to support their use. The majority of information available in the literature relates to the hypothesised action of chemical constituents or studies in animals. Valerian appears to be the only product for which more than one trial has been conducted on humans, a number of

whom reported a sedative effect. A review by Stevinson and Ernst (2000) found some evidence of efficacy in long-term studies (14–28 nights of therapy) but inconclusive evidence in short-term trials (1–4 nights’ therapy). In addition, the trials were often of short duration, used volunteers or patients with different criteria, and were usually methodologically poor. A number of branded products containing combinations of herbal ingredients are available OTC.

Practical prescribing and product selection Prescribing information relating to medicines for insomnia in the section ‘Evidence base for non-prescription medicine’ is discussed and summarised in Table 4.9 and useful tips relating to patients presenting with insomnia are given in Hints and Tips Box 4.2. Both the antihistamines that are used for insomnia are first-generation antihistamines and interact with other sedating medicines, resulting in potentiation of sedation. Additionally, they possess antimuscarinic side-effects, which commonly lead to dry mouth and possibly to constipation. It is these antimuscarinic properties that mean patients with glaucoma and prostate enlargement should ideally avoid their use as it could lead to increased intraocular pressure and precipitation of urinary retention. Both diphenhydramine and doxylamine should not be used for more than 10 consecutive nights. Patients should also be warned about possible next day sedation

Table 4.9 Practical prescribing: Summary of medicines for insomnia

Medicine Diphenhydramine Doxylamine

Use in children

Likely side-effects

Drug interactions of note

Patients in whom care should be exercised

Pregnancy

>12 years

Dry mouth, sedation and grogginess next day

Increased sedation with alcohol, opioid analgesics, anxiolytics, hypnotics and antidepressants

Open-angle glaucoma, prostate enlargement

Category A, although manufacturers advise avoidance

HINTS AND TIPS BOX 4.2: INSOMNIA Antihistamines

Tolerance can develop with continuous use. It is recommended that they should not be used for more than 10 consecutive nights. Patients should also be aware of possible next-day sedation

Patients who self-treat for depression

St John’s Wort (hypericum) is used by many patients to treat depression. There is a growing body of evidence that it is more effective than placebo for mild depression and is comparable in effect to tricyclic antidepressants. However, pharmacists should not recommend it routinely. If depression is suspected then the patient should be referred for further assessment. St John’s Wort also interacts with other medicines, including warfarin, SSRIs, antiepileptics, digoxin, cyclosporin, theophylline and some contraceptives © 201 2012 2 Els Elsevi evier er Aus Austra tralia lia

Insomnia as both antihistamines have long half-lives (8–10 hours), which are even longer in older populations.

Diphenhydramine Diphenhydramine is approved only for adults and children over 12 years of age, and one capsule or tablet should be taken 20 minutes before going to bed.

Doxylamine Adults and children over 12 years of age should take one or two tablets 20 minutes before bedtime.

References Paine S, Gander P, Harris R et al 2005 Prevalence and consequences of insomnia in New Zealand: disparities between Maori and non-Maori. Australian and New Zealand Journal of Public Health 29:22–28 Pearson N J, Johnson L L, Nahin R L 2006 Insomnia, trouble sleeping, and complementary and alternative medicine: Analysis of the 2002 national health interview survey data. Archives of Internal Medicine 166(16):1775–1782 Rickels K, Ginsberg J, Morris R et al 1984 Doxylamine succinate in insomniac family practice patients: a double-blind study. Current Therapeutic Research 35:532–540 Rickels K, Morris R J, Newman H et al 1983 Diphenhydramine in insomniac family practice patients: a double-blind study. Journal of Clinical Pharmacology 23:234–242 Sjoqvist F, Lasagna L 1967 The hypnotic efficacy of doxylamine. Clinical Pharmacology and Therapeutics 8:48–54 Stevinson C, Ernst E 2000 Valerian for insomnia: a systematic review of randomized clinical trials. Sleep Medicine 1:91–99 Teutsch G, Mahler D L, Brown C R et al 1975 Hypnotic efficacy of diphenhydramine, methapyrilene and

91

pentobarbital. Clinical Pharmacology and Therapeutics 17:195–201 Tiller J W G 2003 The management of insomnia: an update. Australian Prescriber 26:78–81

Further reading Adam K, Oswald I 1986 The hypnotic effects of an antihistamine: promethazine. British Journal of Clinical Pharmacology 22:715–717 Anderson E G 1992 Night people: avoiding the quick fix for insomnia. Geriatrics 47:65–66 Gillin J C, Byerley W F 1990 The diagnosis and management of insomnia. New England Journal of Medicine 322:239–248 Mellinger G D, Balter M B, Uhlenhuth E H 1985 Insomnia and its treatment. Prevalence and correlates. Archives of General Psychiatry 42:225–232 Newall C A, Anderson L A, Phillipson J D 1996 Herbal medicines: a guide for health-care professionals. Pharmaceutical Press, London NPS Prescribing Practice Review 49: Management options for improving sleep. [Online] Available: http:// www.nps.org.au/health_professionals/publications/ prescribing_practice_review/current/prescribing_practice_ review_49 [1 August 2010] Sproule B A, Busto U E, Buckle C et al 1999 The use of non-prescription sleep products in the elderly. International Journal of Geriatric Psychiatry 10:851–857

Web sites National Sleep Foundation: www.sleepfoundation.org/ Newcastle Sleep Disorders Centre: www.newcastle.edu.au/ centre/nsdc/pamphlets.html

Further resources for this chapter are available online at: http://evolve.elsevier.com/AU/Newby/community/


4

92


Self-assessment questions The following questions are intended to supplement the text. Two levels of question are provided; multiple choice questions and case studies. The multiple choice questions are designed to test factual recall and the case studies allow knowledge to be applied to a practice setting.

4.6. Which trigger sign or symptom warrants referral?

Multiple choice questions

a. Headache lasting 7 to 10 days b. Headache described as ‘vice like’ c. Headache associated with the workplace environment d. Headache in a child under 12 with no sign of infection e. Headache associated with fever

4.1. An important neurotransmitter in the pathogenesis of migraine is: a. b. c. d. e.

Histamine 5HT Dopamine Acetylcholine Adrenaline

4.7. The amount of sleep needed with increasing age: 4.2. Dystonic reactions are a rare side-effect of metoclopramide that occur most commonly in which group of patients? a. b. c. d. e.

Males over 40 years of age Females over 40 years of age Females over 65 years of age Females under 20 years of age Males under 20 years of age

a. Increases b. Decreases c. Stays the same 4.8. Which of these statements is true when giving advice on sleep hygiene? a. b. c. d. e.

4.3. Cluster headache could be best described as: a. Bilateral piercing pain behind the eyes that lasts for a matter of only minutes b. Unilateral piercing pain behind an eye that lasts for a matter of only minutes c. Unilateral orbital piercing pain with associated unilateral nasal congestion d. Bilateral orbital piercing pain with associated nasal congestion e. Bilateral orbital piercing pain only 4.4. Nausea and vomiting are associated with: a. b. c. d. e.

Tension headache Trigeminal neuralgia Cluster headache Subarachnoid haemorrhage Sinusitis

Golden rod Tolu balsam Burdock Mugwort Passion flower

Questions 4.9 to 4.11 concern the following anatomical locations of the brain: A. B. C. D. E.

Orbital Temporal Occipital Generalised Unilateral and frontal

Select, from A to E, which of the above locations: 4.9. Is associated with cluster headache 4.10. Is associated with subarachnoid haemorrhage 4.11. Is associated with tension headache

4.5. What herbal remedy is used to help treat insomnia? a. b. c. d. e.

Drinking coffee and tea is OK before bedtime Try to vary the time when you go to bed Sleep in a warm room Try not to nap through the day Take moderate exercise before going to bed

Questions 4.12 to 4.14 concern the following medicines: A. B. C. D. E.

Domperidone Doxylamine Metoclopramide Oral contraceptive Metoclopramide with paracetamol

© 2012 Elsevier Australia

Self-assessment questions Select, from A to E, which of the above medicines: 4.12. Should be avoided by patients taking paracetamol 4.13. Is only licensed in combination with paracetamol for nausea associated with migraine 4.14. Has been linked to causing migraine 4.15. Which of the following is a feature of a tension headache: a. b. c. d. e.

Dull ache, not normally throbbing Occurs about the same time each day Unilateral Worse in the night Worse when you lie down

4.16. Which of the following is not a symptom of the aura associated with migraine: a. b. c. d. e.

93

4.18. Which of the following is a primary headache disorder: a. b. c. d. e.

Alcohol-induced headache Analgesic-overuse headache Cervicogenic headache Chronic post-traumatic headache Migraine with aura

4.19. Which of the following are true regarding the non-prescription treatments for insomnia: a. They have short half-lives b. They should not be used in patients with prostate enlargement c. They should not be used for more than 14 consecutive nights d. They should be taken 1–2 hours before bedtime e. They are third-generation antihistamines 4.20. Which of the following is a commonly reported trigger of migraine attacks:

Taste disturbances Flashing lights Pins and needles Scotomas Zig-zag lines

4.17. Which statement relating to headache is true: a. Headache with aura is the most common type of migraine headache b. Cluster headache is more common in women than men c. Temporal arteritis affects mainly middle-aged men d. Migraine is more common in women than men e. Cluster headaches are usually bilateral

a. Alcohol b. Lying down c. Staring at computer screens for extended periods d. Over eating e. Menstrual cycle


4

94


Case studies CASE STUDY 4.1 Mr AM, a male patient in his early thirties, presents to the pharmacy at lunch time complaining of headaches. The following questions are asked and responses received. Information gathering

Data generated

Presenting complaint (possible questions) What symptoms/describe the symptoms How long had the symptoms Other symptoms Where exactly Any time worse/better Severity of pain (1–10) Frequency of pain Eye test; recent trauma Previous history of presenting complaint Past medical history Drugs (OTC, Rx and compliance)# Allergies

General aching feeling all over the head Had for the last week No problems with lights, etc. No sickness. No recent trauma All over the head Seems to get worse as day goes on 4 Most of the time Eyes OK, no need for glasses; no None None None Penicillin

Social history Smoking Alcohol Drugs Employment Relationships Family history On examination

Non-smoker Drinks red wine (a couple of glasses each night) Works in marketing. Job OK but busy with new promotion Married with two young children Not known Not applicable

Epidemiology dictates that tension-type headache is the most likely cause in primary care. However, other conditions are possible and are noted below: Probability

Cause

Most likely Likely Unlikely

Tension headache Migraine, sinusitis, eye strain Cluster headache, temporal arteritis, trigeminal neuralgia, depression Glaucoma, meningitis, subarachnoid haemorrhage, raised intracranial pressure

Very unlikely

Diagnostic pointers with regard to symptom presentation The expected findings for questions when related to the different conditions that can be seen by community pharmacists are summarised on the following page.


Case studies

Duration Tension-type headache

Can last days

Migraine

Average attack lasts 24 hours

Cluster headache

1–3 hours

Sinusitis

Days

Eye strain

Days

Temporal arteritis Trigeminal neuralgia Depression

Hours to days Minutes

Glaucoma

Days to months Hours

Meningitis

Hours to days

Subarachnoid haemorrhage Raised intracranial pressure

Minutes to hours Days to months

Timing and nature

Relative severity (pain score from 0 to 10)*

Location

95


Who is affected

Stress due to changes in work or home environment Food (in 10% of sufferers) & family history

All age groups and both sexes equally affected Three times more common in women. Rare in children

Three to five times more common in men Adults

Symptoms worsen as day progresses. Non-throbbing pain Associated with menstrual cycle and weekends. Throbbing pain & nausea. Dislike of bright lights and loud noise Attacks occur at same time of day. Intense boring pain Dull ache that starts off being unilateral Aching

Bilateral & most often at back of head

2–5

Usually unilateral

4–7

Unilateral

>7

Alcohol

Frontal

2–6

Valsava movements

Frontal

2–5

All ages

Variable

Unilateral around temples Face

3–6

Close vision work None

>7

None

Adults

Generalised

2–5

Social factors

Adults

Unilateral and orbital

>7

Darkness

Older adults

Generalised

>7

None

Children

Variable

Occipital

>7

None

Adults

Worse in the mornings

Variable

>4/5

None

Older adults

Lancing pain at any time Non-throbbing pain Often in the evening and sudden onset Associated with systemic infection

Elderly

*Scores set by the authors and are not evidence-based When this information is applied to that gained from our patient (below) we see that his symptoms most closely match tension-type headache, which

may (or may not) be triggered by extra pressure at work. Depression is also a possibility, although less likely.


4

96


Duration

Timing and nature

Location

Severity (pain score from 0 to 10)


Who is affected

Tension

✓

Migraine

✓

✓

✓

✓

✓

Cluster

✗

✗

✗

✓

✗

✗

✗

✗ ?

✓?

✗

Sinusitis

✓

✓?

✗

✓

✗

✓

Eye strain

✓

✓

✗

✓

✓

✓?

✗

✓

✗ N/A

✓

Temporal arteritis Trigeminal neuralgia

✗

✗

✗

✗

N/A

✓

✓

✗

Depression

✓

✓?

✓

✓

✓?

✓

Glaucoma

✗

✗

✗

✗

✗

Meningitis

✗

✗

✓

✗

✗ N/A

Subarachnoid haemorrhage

✗

✗

✗

✗

N/A

✓

Raised intracranial pressure

✓

✗

✓

✓

N/A

✗

Danger symptoms/signs (trigger points for referral) As a final double check it might be worth making sure the person has none of the ‘referral

✗

signs or symptoms’; this is the case with this patient.

Headache unresponsive to analgesics

Not yet tried

Headache in children under 12 with no signs of systemic infection or who have a stiff neck or skin rash Headache occurs after recent (1 to 3 months) trauma injury

✗

Headache that has lasted for more than 2 weeks

✗

Nausea and/or vomiting in the absence of migraine symptoms

✗

Neurological symptoms, if migraine excluded, especially change in consciousness

✗

New or severe headache in patients over 50

✗

Progressive worsening of headache symptoms over time

✗

Very sudden and/or severe onset of headache

✗


✗

Case studies

97

CASE STUDY 4.2 Mrs PC, a 36-year-old woman, asks you for something to treat her headache. On questioning you find out the following: ● She has had the headache for about 5 days. ● The pain is located mainly behind left eye and front of head but is also at back of head. ● Mrs PC is experiencing aching, but no sickness or visual disturbances. ● She has tried paracetamol, which helps for a while but the pain comes back after a few hours. ● She has not had this type of headache before.

● Work at the moment is busy because of a conference she is organising. ● She takes nothing from her GP except the mini-pill (levonorgestrel). ● There is no recent history of head trauma. ● The pain gets worse as the day goes on. a. What is the likely differential diagnosis, and why? b. From the above responses, which symptoms allowed you to rule out other conditions?

4

CASE STUDY 4.3 Mr FD, a 55-year-old man, asks you for a strong painkiller for his headache. He has had the headache for a few days but it doesn’t seem to be going away. After talking to Mr FD, you find out the following: ● The headache is located in the frontal area and is bilateral. ● He describes the pain as throbbing. ● He has never had a headache like this before. ● He has not suffered from migraines in the past. ● There are no associated symptoms of upper respiratory tract infection.

● He is retired and has a non-stressful lifestyle. ● He has tried paracetamol but without much success. ● He takes atenolol for hypertension. a. Using the information on epidemiology and data on signs and symptoms of each condition from Case Study 4.1, what is the likely differential diagnosis? b. What extra questions could you ask to support your diagnosis?


98


CASE STUDY 4.4 Mrs SP, the wife of a 54-year-old man, enters the pharmacy and asks for Panadeine (paracetamol 500 mg/ codeine 8mg); her husband has a bad ‘migraine’ and her neighbour told her it was for ‘strong’ pain. Information gathering

Presenting complaint (Possible questions) Describe symptoms

Data generated

Allergies

Very painful headache. Worst towards the back of the head; feels nauseous and vomited twice but vomiting seems to have subsided 12–24 hours Very painful (7–8 out of 10) Just said it is very painful Can’t do anything. Painful even to do ‘normal’ things like shower, dress, etc. Not had eye test for a year but eyes OK; no recent trauma No Tried a couple of paracetamol but did not seem to ease the pain None Hypercholesterolaemia Simvastatin/ezetimibe 40 mg/10 mg – one at night Uses antihistamines OTC during spring/summer No allergies to medicines, only hayfever

Social history Smoking Alcohol Drugs Employment Relationships Family history On examination

Smokes 20 a day Occasional Executive for a marketing firm Approx 20 units a week alcohol Married None for presenting complaint He generally looks tired and pain is aggravated by light

How long had you had the symptoms Severity of pain Nature of the pain Other symptoms/provokes Eye test; recent trauma Any symptoms before headache Tried anything for the pain Previous history of presenting complaint Past medical history Drugs (OTC, Rx and compliance)

a. Given the information the lady has given you, would you recommend Panadeine?

Answers to multiple choice questions 4.1 = b 4.2 = d 4.3 = c 4.4 = d 4.5 = e 4.11 = D 4.12 = E 4.13 = A 4.14 = D 4.15 = a

b. Would you recommend anything else at this stage to treat the headache?

4.6 = d 4.7 = b 4.8 = d 4.9 = A 4.10 = C 4.16 = a 4.17 = d 4.18 = e 4.19 = b 4.20 = e

Answers to case study questions – see page 308 © 2012 Elsevier Australia