Public health danger as OTC antibiotics use soars
By Lilian Anekwe
Selling antibiotics over the counter leads to a huge increase in their use that should rule out any further rollout of the policy, GP researchers conclude.
They warned of serious consequences for public health after finding that overall use of chloramphenicol jumped by 48% in the first two years after it went on sale in pharmacies in 2005.
The figures are closely in line with those from a Pulse investigation last December, which found overall use of chloramphenical had leapt by 60% since reclassification.
The MHRA has repeatedly insisted that reclassifying a antibiotics would not lead to a surge in their general use and has also reclassified azithromycin as a pharmacy product, and proposed trials of OTC trimethoprim.
But the new University of Oxford study provides strong evidence to undermine those claims.
GP prescriptions for topical chloramphenicol fell slightly from 2.3 million in 2004 to 1.9 million in 2007, a reduction of 15.5%.
Overall consultation rates also fell and the proportion of consultations for which a delayed prescription was issued increased by 14.7% for which no prescription was issued by 14.5%.
But OTC sales of the drug grew steadily following its reclassification, with 1.1 million additional packs used overall in 2007 than in 2004.
Study leader Dr Peter Rose, lecturer at the Department of Primary Care at the University of Oxford, said: ‘Making an antibiotic available OTC increases its use substantially. This is in conflict with public health messages on antibiotic resistance, the evidence on appropriate use and clinical effectiveness.
‘There should be considerable thought before making any other antibiotics, including trimethoprim, available without prescription.'
The reclassifications of trimethoprim and nitrofurantoin are still under consultation by the MHRA.
But in his annual report last month the Chief Medical Officer Sir Liam Donaldson warned against switching any more antibiotics ‘unless there is careful consideration of the potential public health consequences'.
Dr Anthony Brzezicki, a GP in Croydon and prescribing lead for Croydon PCT, said: ‘People using chloramphenicol OTC often get sorer eyes for longer and come back for stronger antibiotics.
‘If that starts to happen with trimethoprim and nitrofurantoin we will be completely scuppered. But I don't think the regulators are that concerned with what GPs on the ground think.'Use of chloramphenical antibiotic eye drops has risen 48% since the drug went OTC How concerns over OTC antibiotics have grown
August 2008 – Pulse reports microbial experts react furiously to MHRA proposal to reclassify trimethoprim, branding it potentially ‘disastrous'
November 2008 – MHRA says it is now considering large-scale pilot trials of trimethoprim availability OTC, under patient group directions
December 2008 – Pulse investigation reveals efforts to control antimicrobial resistance are being undermined by a 60% rise in use of chloramphenicol
April 2009 – Primary care research finds 48% net increase in chloramphenicol use after OTC switch, prompting warnings over public health consequences