In patients allergic to penicillin, consider second and third generation cephalosporins for life threatening infections

doi:10.1136/bmj.39372.829676.47

BMJ 2007;335:991 (10 November), doi:10.1136/bmj.39372.829676.47

Practice

Change Page

In patients allergic to penicillin, consider second and third generation cephalosporins for life threatening infections

Scott Pegler, principal pharmacist, medicines information manager¹, Brendan Healy, specialist registrar in infectious diseases and microbiology²

¹ Morriston Hospital, Swansea NHS Trust, Swansea SA6 6NL , ² NPHS Wales, Microbiology Department, University Hospital of Wales, Cardiff CF14 4XW

Correspondence to: S Pegler scott.pegler@swansea-tr.wales.nhs.uk

The first 150 words of the full text of this article appear below.

Introduction

Key points

True penicillin allergy occurs in 7-23% of patients who givea history of penicillin allergy

The frequently cited figureof 10% cross reactivity between penicillin and cephalosporinsis an overestimate

Cross reactivity between penicillins andsecond and third generation cephalosporins is low and may belower than the cross reactivity between penicillins and unrelatedantibiotics

Anaphylaxis with cephalosporins is rare (0.1-0.0001%)

Inlife threatening infections such as bacterial meningitis, septicaemia,and severe respiratory tract infections, consider using secondand third generation cephalosporins even in patients with ahistory of penicillin allergy

The clinical problem

Many patients claim to be allergic to penicillin. For thoseconfirmed as being truly allergic (type 1 allergy, with featuresof urticaria, pruritic rash, etc), the cited overall rate of10% cross reactivity between penicillin and cephalosporins isan overestimate.¹ For life threatening infections such as bacterialmeningitis, septicaemia, and severe respiratory tract infectionsin which a non-cephalosporin antibiotic . . . [Full text of this article]