Prescribing at a Glance E-Book

Sarah Ross

• Herausgeber: John Wiley & Sons
• Kategorie: Fachliteratur
• Serie: At a Glance
• Sprache: Englisch

Seitenzahl: 204

Veröffentlichungsjahr: 2014

Beschreibung

Prescribing at a Glance The market-leading at a Glance series is used world-wide by medical students, residents, junior doctors and health professionals for its concise and clear approach and superb illustrations. Each topic is presented in a double-page spread with clear, easy-to-follow diagrams, supported by succinct explanatory text. Covering the whole medical curriculum, these introductory texts are ideal for teaching, learning and exam preparation, and are useful throughout medical school and beyond. Everything you need to know about Prescribing...at a Glance! The principles of drug therapies are fundamental to medical practitioners in all branches; but are often difficult to get to grips with. Prescribing at a Glance addresses the most common uses of prescription drugs, and follows progress from dose calculation and administration to monitoring the effects in the treatments of major presenting problems. With a focus on prescribing, this user-friendly guide helps practitioners to develop crucial knowledge and skills, including establishing accurate drug histories, planning appropriate therapies, writing safe and legal prescriptions, critically appraising the prescribing of others, patient support, accessing reliable information about medicines, and detecting adverse drug reactions. Prescribing at a Glance: * Features detailed and high-quality colour illustrations throughout * Includes examples of common prescribing errors, practice prescriptions and calculations * Follows the structure of the WHO Good Prescribing Guide, and corresponds to the core curriculum of the British Pharmacological Society * Is the perfect guide to help you prepare for the Prescribing Skills Assessment (PSA) From the series that brought you Medical Pharmacology at a Glance, and designed to help those in the later stages of their medical training become adept at the skills required for a vital yet often confusing subject, Prescribing at a Glance will help you fill in any knowledge gaps with simple step-by-step instructions, and clear, easy- to-remember guidelines. All content reviewed by students for students Wiley-Blackwell Medical Education books are designed exactly for their intended audience. All our books are developed in collaboration with students, which means our books are always published with you, the student, in mind.

Leseprobe

This edition first published 2014 © 2014 John Wiley & Sons, Ltd

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Library of Congress Cataloging-in-Publication Data is available

9781118257319

A catalogue record for this book is available from the British Library.

Cover image: Science Photo Library © Mark Thomas/Science Photo Library

Cover design by Meaden Creative

Set in 9.5/11.5pt MinionPro by Toppan Best-set Premedia Limited

1 2014

Contents

Preface   v

How to use your textbook   vi

About the companion website   ix

Part 1

Basic principles of prescribing   1

1   Introduction: principles of good prescribing2

2   Revision: pharmacokinetics4

3   Using the British National Formulary6

4   Taking a medication history8

5   Reviewing current medicines10

Part 2

Drug selection   13

6   How to choose a drug14

7   How to choose frequency15

8   How to choose a dose16

9   How to choose route of administration and formulation18

10 How to choose duration of treatment, define treatment objectives and measure outcomes20

11 Assessing suitability of treatment regimens for patients21

12 Worked example 1: Chapters 6–1122

13 Worked example 2: Chapters 6–1123

Part 3

Prescribing for special groups   25

14   Prescribing in liver disease26

15   Prescribing in renal disease28

16   Prescribing in children30

17   Prescribing in the elderly32

18   Prescribing in pregnancy and breast feeding34

Part 4

Logistics of prescribing   37

19   How to write a drug prescription38

20   Communicating with patients about medicines40

21   Therapeutic drug monitoring42

22   Dealing with adverse drug reactions44

23   Avoiding drug interactions (drugs, food and alternative medicines)46

24   Avoiding prescribing errors48

iii

Part 5

Specific drug groups  51

25   Using drugs for the gastrointestinal system52

26   Using drugs for the cardiovascular system I54

27   Using drugs for the cardiovascular system II56

28   Using drugs for the cardiovascular system III58

29   Using drugs for the respiratory system60

30   Using drugs for the neurological system I62

31   Using drugs for the neurological system II64

32   Using drugs for infection66

33   Using drugs for the endocrine system I68

34   Using drugs for the endocrine system II70

35   How to use drugs for the musculoskeletal system72

36   Using drugs in haematology and oncology74

37   Using drugs in anaesthesia76

38   An approach to common prescribing requests I78

39   An approach to common prescribing requests II80

Appendix   Cross references to Prescribing Scenarios at a Glance    81

Index    82

iv

Preface

Prescribing is a core skill for all doctors, and increasingly for non-medical staff. It is a difficult skill to learn. A great deal of attention has been paid to prescribing skills in recent times, and the new Prescribing Safety Assessment has focussed minds on ensuring that new graduates are ready to prescribe safely. I hope that this book will be helpful to students and doctors learning to prescribe. As with many skills, practice is essential, and you should take every opportunity to plan the exact prescription of a drug for patients that you see. Prescribing Scenarios at a Glance provides useful practical examples to work through that are referenced within this text. This book has been written with new graduates embarking on the Foundation Programme in mind, and therefore focuses on mainly hospital-related prescribing; however, many of the principles extend to primary care situations. A highly practical approach has been taken, but will not describe all possible ways to look at a prescribing problem. Seek out the advice of experienced colleagues, whether doctors, nurses or pharmacists, who can provide guidance to the novice prescriber.

This book is deliberately concise, and may be supplemented by Medical Pharmacology at a Glance which gives a useful summary of drug mechanisms of action.

Acknowledgements

Thanks to Dr Mary Joan Macleod for critical review and suggestions.

Further reading

Joint Formulary Committee (2013). British National Formulary 66th ed. British Medical Association and Royal Pharmaceutical Society of Great Britain, London.

Richards D, Coleman J, Reynolds J, Aronson J (2011). Oxford Handbook of Practical Drug Therapy. Oxford University Press, Oxford.

Nicholson TRJ, Singer DRJ (eds) (2014). Pocket Prescriber. CRC Press, London.

v

How to use your textbook

Features contained within your textbook

Each topic is presented in a double-page spread with clear, easy-to-follow diagrams supported by succinct explanatory text.

Your textbook is full of illustrations and tables.

vi

Section not available in this digital edition

vii

Section not available in this digital edition

viii

About the companion website

ix

Basic principles of prescribing

Part 1

Chapters

1      Introduction: principles of good prescribing    2

2      Revision: pharmacokinetics    4

3      Using the British National Formulary    6

4      Taking a medication history    8

5      Reviewing current medicines    10

Don’t forget to visit the companion website for this book www.ataglanceseries.com/prescribing to do some practice MCQs and case studies on these topics.

1

1

Introduction: principles of good prescribing

Box 1.1   Prescribing framework

Ideally, you should build up a ‘personal formulary’ of drugs for common situations.

When choosing drugs to use consider the following:

What is the diagnosis?

What are you trying to achieve?

Make a list of possible drug classes that could do this

Compare them according to safety, efficacy, suitability and cost

Select a first-choice drug class for this situation

Compare drugs within the class in the same way

Select a first-choice drug for this situation

When you are treating a patient with this type of problem:

Ensure that you have defined the patient’s problem and specified the therapeutic objective

Consider your first-line drug from your personal formulary (or go through the steps above)

Check suitability of the first-choice drug for this patient: Is it likely to be effective? Is it likely to be safe?

Is the form and dose suitable? Is the duration suitable?

If so, start treatment. If not, reconsider. Would a change to the standard regimen for the drug help?

Would a different drug from the same class be suitable? Do you need to go back to the beginning of the process and select a different drug class for this patient?

Once a drug and regimen is selected, start treatment

Give information to the patient

Monitor/stop treatment as appropriate

Worked examples can be found in Chapters 12 and 13.

2

Part 1   Basic principles of prescribing

Prescribing at a Glance, First Edition. Sarah Ross. © 2014 John Wiley & Sons, Ltd. Published 2014 by John Wiley & Sons, Ltd. Companion website: www.ataglanceseries.com/prescribing

P

rescribing is more than writing a drug order on a chart and requires a subset of competencies involving knowledge, judgement and skill. These skills include medication history

taking, reviewing medicines, choosing a new medicine, assessing the suitability of a drug regimen for a patient, writing a prescription, communicating with a patient about their medicines, monitoring drug effects, and dealing with drug-related problems. Prescribing is currently undertaken in a complex healthcare environment with growing numbers of medicines, ageing patients who have increasing numbers of comorbidities, and dwindling resources. Studies have highlighted adverse drug effects and prescribing errors as significant issues. These issues highlight the need for careful and thoughtful prescribing by all prescribers.

Prescribing well is difficult. Opportunities to practice as a student are limited, and looking back many doctors describe an insufficient emphasis on the practical aspects of prescribing in the undergraduate curriculum. This book is one attempt to help by providing clear, concise guidance on how to prescribe safely and effectively, and should be used in combination with practical examples. It could also be helpful as a guide for new graduates as they learn ‘on the job’.

One of the ways to ensure good prescribing is to use a frame-work such as the one described in Box 1.1, which is based on the World Health Organization Guide to Good Prescribing. The steps are outlined in individual chapters of this book. As you develop from a novice into an expert prescriber, the steps will become automatic; however, there will still be times when it is helpful to deliberately work through each one to ensure a good choice is made.

Another element of learning to prescribe is to watch how established practitioners approach it, and to ask why they have selected a particular treatment regimen. This can give insight into the prescribing process, but be careful to consider their choice critically.

Be wary about drug information, particularly if supplied by the manufacturer for marketing purposes. Where possible, seek out unbiased data.

Further Reading

De Vries TPG, Henning RH, Hogerzeil HV, Fresle DA. (1994) Guide to Good Prescribing: A Practical Manual. World Health Organization, Geneva.

3

Chapter 1   Introduction: principles of good prescribing

4

Part 1  Basic principles of prescribing

2

Revision: pharmacokinetics

Figure 2.1    Pharmacokinetics of a single oral dose.

Prescribing at a Glance, First Edition. Sarah Ross. © 2014 John Wiley & Sons, Ltd. Published 2014 by John Wiley & Sons, Ltd. Companion website: www.ataglanceseries.com/prescribing

P

harmacokinetics describes the way in which drugs are pro-

cessed by the body through absorption, distribution, metab-

olism and excretion. Understanding these processes helps

prescribers choose appropriate routes, doses and frequencies of admission, as well as avoid adverse drug reactions in vulnerable populations.

Absorption