[10] Whether such reclassification is appropriate for an antimicrobial agent is unclear. Ophthalmic chloramphenicol was the first antibiotic available for purchase OTC in the UK and was indicated for the treatment of acute bacterial conjunctivitis. The eye drops were first marketed in June 2005 and the ointment in July 2007, both as P medicines. The drug is routinely prescribed by primary care prescribers[11] for suspected cases of infective conjunctivitis and is the recommended first-line

treatment.[12] Prior to OTC availability, community pharmacists were limited to selling antiseptic preparations, such as propamidine and dibrompropamidine-based Natural Product Library cell assay products, for ophthalmic infections.[13] The proposal to make ophthalmic

chloramphenicol available OTC was welcomed by various groups of healthcare professionals and the public following widespread consultation. At the time the benefit of improved and timely access to treatment outweighed the risks associated with wider accessibility,[14, 15] although concerns regarding check details inappropriate over-supply, misdiagnosis by pharmacists and the emergence of increased bacterial resistance were raised.[16] Since the launch of OTC ophthalmic chloramphenicol two main issues have come to light. First, pharmacy availability of ophthalmic chloramphenicol has been shown to have no impact on prescription supply for the same drug, and overall there was a substantial increase in the supply of chloramphenicol in primary care in the first 3 years following reclassification.[17, Thiamet G 18] Whether this situation remained

the same beyond 3 years is unknown. Secondly, there is increasing clinical evidence that topical antibiotics are of limited benefit in infective conjunctivitis in primary care.[19] Given that the condition is, in most cases, self-limiting[20, 21] and that restricting use of antibiotics minimises unnecessary treatment and emergence of resistance,[22] the current consensus in managing these patients is to adopt the practice of ‘no or delayed antibiotic’ supply.[23] Recent evidence suggests this may have impacted on the prescribing of ophthalmic chloramphenicol by GPs[24] but whether supply OTC was affected remains unclear. The aims of the study, therefore, were to (i) quantify the sales of OTC ophthalmic chloramphenicol from all community pharmacies in Wales and investigate the impact on primary care prescriptions up to 5 years after reclassification and (ii) investigate the temporal relationship between items supplied OTC and on NHS primary care prescriptions. The study had an ecological design and involved a retrospective analysis of prescription data and OTC sales data for ophthalmic chloramphenicol supplied in Wales. Prescription data were extracted from CASPA.net (Comparative Analysis System for Prescribing Audit), an NHS Wales data store for primary care prescribing data.