Experience in Monitoring Drug Reactions in Outpatients

Abstract

The Kaiser-Permanente Drug Reaction Monitoring System is, to our knowledge, the first epidemiologic adverse drug reaction study that has systematically monitored ambulatory patients. Prescriptions dispensed and clinic diagnoses made at the Kaiser-Permanente medical center in San Francisco are recorded in a central patient computer medical record. Rates of untoward events developing in users and nonusers of drugs are computed and compared. Drug-event associations are evaluated as to whether a cause and effect relationship is likely. Analysis of data obtained from over 220,000 clinic and pharmacy visits made by about 75,000 patients during the period, July to December 1969, provided information about outpatient drug usage patterns and evidence both for the existence of certain adverse drug reactions and against the occurrence of others.