Prescribingin PregnancyFourth edition

Edited by

Peter RubinNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Margaret RamsayNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Prescribing in Pregnancy

Prescribingin PregnancyFourth edition

Edited by

Peter RubinNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Margaret RamsayNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

C© 2000 BMJ Publishing GroupC© 2008 by Blackwell PublishingBMJ Books is an imprint of the BMJ Publishing Group Limited, used under licence

Blackwell Publishing, Inc., 350 Main Street, Malden, Massachusetts 02148-5020, USABlackwell Publishing Ltd, 9600 Garsington Road, Oxford OX4 2DQ, UKBlackwell Publishing Asia Pty Ltd, 550 Swanston Street, Carlton, Victoria 3053, Australia

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All rights reserved. No part of this publication may be reproduced, stored in a retrievalsystem, or transmitted, in any form or by any means, electronic, mechanical,photocopying, recording or otherwise, except as permitted by the UK Copyright,Designs and Patents Act 1988, without the prior permission of the publisher.

First published 1987Second Edition 1995Third Edition 2000Fourth Edition 2008

1 2008

Library of Congress Cataloging-in-Publication DataPrescribing in pregnancy / edited by Peter Rubin, Margaret Ramsay. – 4th ed.

p. ; cm.ISBN 978-1-4051-4712-5 (pbk.)1. Obstetrical pharmacology. I. Rubin, Peter C. II. Ramsay, M. M., M.D.[DNLM: 1. Drug Therapy. 2. Pregnancy. 3. PharmaceuticalPreparations–administration & dosage. 4. Pregnancy Complications–drug therapy.WQ 200 P932 2007]RG528.P74 2007618.2’061–dc22

2007017554

ISBN: 978-1-4051-4712-5

A catalogue record for this title is available from the British Library

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Blackwell Publishing makes no representation, express or implied, that the drug dosagesin this book are correct. Readers must therefore always check that any productmentioned in this publication is used in accordance with the prescribing informationprepared by the manufacturers. The author and the publishers do not acceptresponsibility or legal liability for any errors in the text or for the misuse ormisapplication of material in this book.

Contents

Contributors, viiPreface, xi

1 Identifying fetal abnormalities, 1Lena M. Macara

2 Treatment of common, minor and self-limitingconditions, 16Anthony J. Avery, Susan L. Brent

3 Antibiotics in pregnancy, 36Tim Weller, Conor Jamieson

4 Anticoagulants in pregnancy, 56Bethan Myers

5 Treatment of cardiovascular diseases, 77Asma Khalil, Pat O’Brien

6 Treatment of endocrine diseases, 89Anastasios Gazis

7 Drugs in rheumatic disease during pregnancy, 98Mary Gayed, Caroline Gordon

8 Psychotropic drugs in pregnancy, 114Neelam Sisodia

9 Managing epilepsy and anti-epileptic drugs duringpregnancy, 126Michael F. O’Donoghue, Christine P. Hayes

10 Treatment of diabetes in pregnancy, 150Nick Vaughan, Kate Morel, Louise Walker

11 Treatment of asthma, 168Catherine Williamson, Anita Banerjee

12 Drugs of misuse, 187Mary Hepburn

v

vi Contents

13 Prescribing for the pregnant traveller, 205Pauline A. Hurley

14 Drugs in breastfeeding, 216Jane M. Rutherford

Index, 231

Contributors

Anthony J. Avery, DM, FRCGPProfessor of Primary Health CareDivision of Primary CareSchool of Community Health

SciencesNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Anita Banerjee, BSc, MBBS, MRCPSpR Endocrinology and Diabetes

MellitusEndocrinology DepartmentHammersmith HospitalLondon, UK

Susan L. Brent, BSc (Hons),MRPharmSDirector of PharmacyRegional Drug and Therapeutics

CentreWolfson UnitNewcastle upon Tyne, UK

Mary Gayed, MBChBAcademic Foundation Year Two

DoctorCity HospitalSandwell and West Birmingham

Hospitals NHS TrustBirmingham, UK

Anastasios Gazis, DM, MRCPConsultant PhysicianDepartment of Endocrinology and

Diabetes

Nottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Caroline Gordon, MRCPReader and Consultant in

RheumatologyDepartment of RheumatologyDivision of Immunity and

InfectionMedical SchoolUniversity of BirminghamBirmingham, UK

Christine P. Hayes, MPhil,BSc (Hons)Epilepsy Specialist NurseNeurosciencesNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Mary Hepburn, BSc, MD, MRCGP,FRCOGConsultant ObstetricianPrincess Royal MaternityGlasgow, UK

Pauline A. Hurley, FRCOGConsultant Obstetrics, Fetal

MedicineThe Women’s CentreJohn Radcliffe HospitalOxford, UK

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viii Contributors

Conor Jamieson, BSc, PhD,MRPharmSPrincipal Pharmacist –

Anti-infectivesHeart of England NHS Foundation

TrustBirmingham, UK

Asma Khalil, MB, BChSenior Research FellowHomerton University HospitalLondon, UK

Lena Macara, MD, FRCOGConsultant ObstetricianThe Queen Mother’s HospitalGlasgow, UK

Kate MorelDiabetes Nurse Specialist ManagerBrighton and Sussex University

Hospitals NHS TurstBrighton, UK

Bethan Myers, MA, MRCP,FRCPath, DTM & HConsultant HaematologistDepartment of HaematologyNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Pat O’Brien, MRCOGObstetric LeadUniversity College London

HospitalsLondon, UK

Michael F. O’Donoghue, BSc, MBBS, MD, MRCP (UK)Consultant NeurologistNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Margaret M. Ramsay, MA, MD,MRCP, FRCOGConsultant in Fetomaternal

MedicineNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Peter C. Rubin, MA, DM, FRCPProfessor of TherapeuticsNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Jane M. Rutherford, DM, MRCOGConsultant in Fetomaternal

MedicineDepartment of ObstetricsNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

Neelam Sisodia, MBBS, MA,MRCPsychConsultant in Perinatal PsychiatryPerinatal Psychiatric ServiceMother and Baby UnitNottingham University HospitalsQueen’s Medical Centre CampusNottingham, UK

N.J.A. Vaughan MA, MD, FRCPConsultant EndocrinologistBrighton and Sussex University

Hospitals TrustRoyal Sussex County HospitalBrighton, UK

Louise Walker, RDSpecialist Diabetes DieticianDiabetes CentreBrighton and Sussex University

HospitalsRoyal Sussex County HospitalBrighton, UK

Contributors ix

Tim Weller, MBChB, MD,FRCPath (deceased)Previously Consultant

MicrobiologistDepartment of MicrobiologyCity HospitalBirmingham, UK

Catherine Williamson,MD, MRCPSenior Lecturer in Obstetric

MedicineHammersmith HospitalImperial CollegeLondon, UK

Preface

The use of drugs in women who are pregnant or breast feeding isa question of fine balance. Harm may befall a baby because a drughas been used, but mother and baby could suffer if a disease goesuntreated. Information about the safe and effective use of drugsin pregnancy has not kept pace with the advances in other areasof therapeutics. Systematic research involving drugs in pregnancyis fraught with ethical, legal, emotional and practical difficultiesand in many cases our knowledge is based on anecdote or smallstudies.

The purpose of this book is to bring together what is knownabout prescribing in pregnancy and to put that information in aclinical context. The first three editions were well received and thishas encouraged us to produce a fourth edition. All chapters havebeen extensively revised or rewritten, with several new authorsbringing their clinical experience of this challenging subject.

We would like to thank Louise Sabir who once again has donemuch behind-the-scenes work in contacting authors.

Acknowledgement

Dr Weller died suddenly while training for the London Marathonshortly after submitting his chapter. He had also contributed tothe third edition and we gratefully acknowledge the professionalmanner in which he approached these tasks.

Peter RubinMargaret RamsayNottingham

xi

CHAPTER 1

Identifying fetalabnormalitiesLena M. Macara

Key points� Days 18–55 postconception is the time of maximal teratogenic

potential when most organs are differentiating� Teratogenic effects of medications may affect both organ structure

and organ function� Detailed ultrasound assessment of the fetus by trained personnel

should detect most major structural abnormalities, but minorabnormalities are often undetected

� Patients at risk of neural tube defects (NTDs) should have 5 mg offolic acid daily for a minimum of 6 wk prior to conception

Introduction

It is estimated that 2–3% of all pregnancies in the United King-dom are affected by congenital abnormality. Almost half of theseabnormalities remain of uncertain aetiology, a further 25% maybe linked to a variety of genetic problems and only 2% are likelyto be associated with environmental factors that include medicinalproducts.

While this is a very small proportion of all birth defects, it is a crit-ical group, since the avoidance of some medications will preventthese abnormalities from occurring. For parents and physicians, itis therefore one of the few areas in which the outcome of preg-nancy can be influenced.

Prescribing in Pregnancy, 4th edition. Edited by Peter Rubin and Margaret Ramsay,c© 2008 Blackwell Publishing, ISBN: 978-1-4051-4712-5.

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