We designed a study to evaluate the pattern and appropriateness of the use of drugs and the laboratory data or procedure in 100 patients (age 1 month-17 years) seen in the emergency department with the diagnosis of otitis media during 178 visits. Patients were selected randomly among those seen during 1983. All patients had usual signs and symptoms of otitis media. Antibiotics prescribed were amoxicillin during 94 visits, trimethoprim/sulfamethoxazole during 33 visits, erythromycin/sulfisoxazole during 14 visits, cefaclor during 5 visits and ampicillin during 3 visits. Due to incomplete dose strength of regimen, only 60% of antibiotic orders were evaluable. The antibiotic doses were within the recommended range in 40% of evaluable cases. Antihistamines and decongestants were used in 28 cases. Analgesics, a variety of ear drops and vinegar irrigation solutions were utilized in 40 cases. Otoscopy was performed in all patients and tympanogram was done in two patients. Ear exudate culture was performed in 5 patients and was found to be positive in 3 cases. All patients were asked to return but only 33 patients came back for a total of 42 follow-up visits to the hospital. Otitis media was reported resolved during 31 visits, resolving during 7 visits, persisting during 3 visits and worsening during 1 visit. The results of this study demonstrate that (1) antibiotic selection was appropriate but the antibiotic orders were incomplete and the doses were frequently out of recommended range; (2) adjunctive drugs seemed to be utilized appropriately; (3) laboratory data and procedures were used appropriately.(ABSTRACT TRUNCATED AT 250 WORDS)