BACKGROUND: Otitis externa is a common clinical problem in general practice and yet there are remarkably few data available on the demographic characteristics of patients with this condition and the approaches used by general practitioners (GPs) in the United Kingdom (UK) to manage it. AIM: To define the descriptive epidemiology of otitis externa in the general population, to describe the first-line drug treatment used by UK GPs, and to determine factors related to second disease episodes. DESIGN OF STUDY: Epidemiological data survey. SETTING: All cases of otitis externa occurring in 1997 in practices contributing data to the UK General Practice Research Database. METHOD: Data were extracted on age, sex, date of episode of otitis externa, treatment prescribed, co-existing diagnoses of eczema and diabetes, referral to ear, nose, and throat departments and occurrence of subsequent episodes of disease. Arbitrarily a second episode of disease was defined as persistence if it occurred at 28 days or fewer after the first episode and recurrence if it occurred at more than 28 days after the first episode. RESULTS: A diagnosis of otitis externa was common in all age groups and, except in the elderly, was more common in females than males. There was an increase in disease episodes at the end of the summer in all age groups except the 60 years and over group. In the majority of cases GPs prescribed ear drops (85%), but a significant proportion of patients were also prescribed oral antibiotics (21%). Referral to secondary care was uncommon (3%). Among patients prescribed ear-drop formulations, those containing both steroid and antibiotic or steroid alone were used most commonly and were associated with the lower rates of disease persistence but not recurrence. Among patients prescribed antibiotics, penicillins were prescribed most commonly. Disease persistence rates, and to a lesser extent disease recurrence rates, were higher in patients prescribed oral antibiotics. CONCLUSION: Otitis externa is a common condition and GPs can expect to see an excess of cases at the end of the summer. Topical ear drops are the most common treatment used in the UK. Patients prescribed steroid or steroid/antibiotic combination ear drops have fewer subsequent consultations for otitis externa over the following 28 days.