Objective: To examine the safety of finasteride as used in general medical practice to treat benign prostatic hypertrophy (BPH).
Patients and methods: Information was collected on 14,772 patients who were included in an observational cohort study conducted using Prescription-Event Monitoring.
Results: Finasteride was reported to have been effective in 60% of the patients in whom an opinion on efficacy was recorded. Impotence or ejaculatory failure was reported in 2.1% of the patients, decreased libido in 1% and gynaecomastia and related conditions in 0.4%. Impotence was the most frequent reason for stopping treatment with finasteride and was the most commonly reported adverse reaction to the drug. Of the patients included in the elderly cohort involved in this study, 819 (5.5%) died; none of these deaths was attributed to finasteride.
Conclusion: Impotence or ejaculatory failure, decreased libido and gynaecomastia in a small proportion of patients were associated with the use of finasteride. The results of this study strongly suggest that this drug is acceptably safe when used in accordance with the current prescribing information.