Ferrous Sulfate Overdose: Interaction Between Finasteride and Hypericum

The document reports the first case of an interaction between finasteride, a medication used for benign prostate hyperplasia, and hypericum (St. John's Wort), which led to decreased efficacy of finasteride. The male patient, whose age was not stated, had been successfully controlling his PSA levels with finasteride for several years. After starting treatment with 900 mg/day of hypericum for depression, his PSA levels increased a few months later. The author suggests that the interaction might be due to hypericum-mediated induction of the CYP3A4 enzyme, which could accelerate the elimination of finasteride, leading to decreased plasma concentrations and reduced efficacy in treating benign prostate hyperplasia or androgenetic alopecia. No outcome of the elevated PSA levels was reported. Prior to this case, no clinically relevant interactions between finasteride and other drugs had been documented, and no previous case reports of such an interaction were found in AdisBase, Medline, Embase, or the WHO ADR database.