POSTMARKETING SURVEILLANCE BY PATIENT SELF-MONITORING - PRELIMINARY DATA FOR SERTRALINE VERSUS FLUOXETINE

Background: There have been no published postmarketing reports compari ng sertraline with another serotonin selective reuptake inhibitor (SSR I) in large-sample, parallel groups. As part of an ongoing postmarketi ng surveillance study, this paper presents preliminary data for a numb er of adverse clinical events reported by outpatients being treated wi th either fluoxetine or sertraline. Method: Using a well-validated met hod developed to signal possible adverse drug reactions, data were col lected on 1577 fluoxetine-treated and 1209 sertraline-treated patients who filled a prescription for either of the two targeted drugs. Pharm acists gave these patients an announcement, part of which served as an entry form, that described the purpose and details of the study. Volu nteers (highly selective) were requested to report during the next mon th via a toll-free telephone interview ''any new or unusual symptoms o r unexpected improvements'' in their health since starting the designa ted medication. Results: Almost 1 (31.4%) of every 3 sertraline-treate d patients called at least once to report one or more adverse clinical events compared with only about 1 (19.7%) of every 5 fluoxetine-treat ed patients. Most of the reported adverse clinical events-but not all- are well-known adverse drug reactions that seem common to SSRIs. Adver se clinical events reported more frequently by sertraline-treated pati ents included urinary, sexual, psychological, neurologic, gastrointest inal, and dermatological complaints. Drug discontinuation was also rep orted more frequently by sertraline-treated patients. Fluoxetine-treat ed patients reported an increased frequency of weight gain and anger o r aggression. Conclusion: These data indicate that many adverse reacti ons known to be induced by fluoxetine are being reported with even gre ater frequency by sertraline-treated patients. Possible interpretation s of these differences are discussed.