ABSTRACT
This study examined the process of adoption and continued use of clarithromycin in actual patient settings during its first year of commercial use by university-affiliated physicians. A prospective observational study of one year's duration was conducted whereby numerous factors associated with the use of clarithromycin were obtained from prescribing physicians. A total of 515 patients received prescriptions for clarithromycin written by 80 physicians. Hospitalized patients received clarithromycin primarily from infectious disease physicians for Mycobacterium avium complex infections. Physicians prescribing clarithromycin for these patients first learned of the drug from a physician colleague. Outpatients received clarithromycin primarily from family practice and emergency medicine physicians. Most patients had bronchitis. Except for pneumonia patients, diagnostic tests were ordered infrequently. Clarithromycin usually was empirically prescribed as a first-line agent along Food and Drug Administration guidelines. Fifty-four percent of physicians' cost estimations were within 10% of the actual cost. Clarithromycin was prescribed by a wide variety of physicians during its first year of commercial availability as first-line empirical therapy for approved indications.