Indication: Finasteride (Propecia) is a 5α-reductase inhibitor indicated for the treatment of male pattern hair loss (androgenetic alopecia) in men only.

Insight:

Dosing:Take 1 tablet once daily.
Dosage forms: 1 mg tablets.
Adverse events:The most common adverse reactions reported in ≥1% of patients treated with finasteride are decreased libido, erectile dysfunction, and ejaculation disorder.
Mechanism of action: Finasteride is a competitive and specific inhibitor of Type II 5a-reductase, an intracellular enzyme that converts the androgen testosterone into DHT
Manufacturer: Merck

Source

LABEL (fda.gov)