Although there have been innumerable studies documenting various aspects of the morbidity caused by diabetes mellitus in the population, very little attention has been paid to patterns of therapeutic management of diabetic patients. The United States Public Health Service Ambulatory Care Data System (USPHS ACDS), a computerized patient information entry and recording system with a complete pharmaceutical record for each patient, was used to compare patterns of pharmaceutical consumption among diabetic patients as opposed to non-diabetic patients in a population of approximately 90,000 individuals. Drug use by diabetics was significantly higher than by non-diabetics. Cardiovascular drug use, in particular, was considerably higher. Substantially higher consumption of anti-lipemic agents, anti-gout drugs, anti-hypertensives, sedatives and tranquilizers was also found in the diabetic population. The higher use of all drugs by diabetics could be partially explained by a demonstrably higher frequency of out-patient visits by diabetics. However this factor alone could not account for very much higher use of certain selective drug groups by the diabetics. In most cases, these selective increases among the diabetics paralleled expected patterns of disease for which those drug groups are prescribed. The investigation of pharmacotherapeutic profiles of the diabetic population adds a new dimension to the epidemiological study of this disease.