Revalidation spoils GP faith in appraisal
The UK drug regulator has failed to provide sufficient warnings to GPs on the potential dangers of flucloxacillin, researchers conclude.
A new prescribing analysis found UK GPs used the antibiotic as often as a decade ago, in 'stark contrast' to progress elsewhere in cutting its use.
The researchers said the UK lagged behind countries such as the US and Australia in issuing strict warnings over the risk of fatal liver reactions and encouraging alternative treatments (see right).
The study, published in August's British Journal of Clinical Pharmacology, found 8.5 users of flucloxacillin per 1,000 developed potentially fatal cholestatic liver disease in the first 45 days of use.
The risk was six times as high in patients over the age of 60 as in those under 60.
But the analysis of records from 1991 to 2002, from the UK general practice research database, found the rate of first-time prescribing of flucloxacillin remained constant at 23 per 1,000 patients.
Study leader Dr Stefan Russman, research fellow at the Boston Collaborative Drug Surveillance Programme in the US, said the UK's Medicines and Healthcare Products Regulatory Agency had issued just a single warning on flucloxacillin during the study period in 1992. 'If you just put out an article which is not followed by any other message you don't expect to change prescribing habits,' he said.
'In Australia a lot of regulatory messages were sent out and they promoted alternative treatments and that did change prescribing habits.'
Dr Russman added: 'It would be appropriate to promote alternative treatments which have the same efficacy but lower risk.'
The MHRA told Pulse it had reviewed the study pre-publication and issued a further warning on flucloxacillin in the November 2004 edition of Current Problems in Pharmacovigilance.
'This association has been recognised for many years and warnings of this risk are included in the product information and the BNF. Flucloxacillin remains an important antibiotic,' said a spokesperson.
But Dr Chaand Nagpaul, member of the GPC prescribing subcommittee and a GP in Edgware, Middlesex, said: 'The risk of cholestatic liver disease is not an issue GPs have received national warnings about so I'm not surprised prescribing behaviour has not changed.'
UK trails US and Australia over flucloxacillin warnings
Dicloxacillin, for which there is little evidence of toxicity, is now recommended as the standard antistaphylococcal oral antibiotic
Flucloxacillin use fell 30 per cent after the government restricted prescribing to severe infections, changed product information, stopped advertising and recommended cephalexin and erythromycin as alternatives
Flucloxacillin still most frequently prescribed antistaphylococcal oral antibiotic with about two million prescriptions a year; the MHRA published single warnings in 1992 and 2004 in Current Problems in Pharmacovigilance
By Emma Wilkinson