Proscar (Finasteride): Uses, Dosage, Side Effects ...
PROSCAR ® (finasteride) Tablets for Oral Administration. DESCRIPTION. PROSCAR (finasteride), a synthetic 4-azasteroid compound, is a specific inhibitor of steroid Type II 5α-reductase, an intracellular enzyme that converts the androgen testosterone into 5α- dihydrotestosterone ().. Finasteride is 4-azaandrost-1-ene-17-carboxamide, N-(1,1-dimethylethyl)-3-oxo-,(5α,17ß)-.