In an open, multi-centre study in general practice, a comparison was made of the efficacy, tolerability and acceptability of a neomycin/dexamethasone preparation administered by metered-dose spray ('Otomize') and a framycetin/gramicidin/dexamethasone preparation ('Sofradex') administered as drops in 60 patients with otitis externa. Patients were allocated at random to receive one or other preparations 3-times daily for 10 days and were followed-up again 14 days after cessation of therapy. Clinical assessments were carried out under observer blind conditions on entry (Day 0) and on Days 10 and 24 of the severity of erythema, swelling and debris in the affected ear(s). A global assessment of clinical outcome was made by the doctor on Day 10. There were no significant differences in the two groups at the start of treatment. Significant improvement occurred in both groups from Day 0 to Day 10 and from Day 10 to Day 24 in all symptoms, with the proportion symptom-free in the 'Otomize' group significantly greater than in the 'Sofradex' group at 24 days, and approaching significance at 10 days. Significantly more patients in the 'Otomize' group were rated as having a good clinical outcome by the physician, and fewer patients experienced discomfort on application. Few side-effects were reported by either treatment group, none necessitating discontinuation of therapy.