Finasteride 1 mg (Propecia)

Finasteride 1 mg for Hair Loss: Dosage, Cost, and What to Expect

Medically reviewed by [Reviewer Name, MD] | Last reviewed: August 2026 | Editorial policy | Dosage hub

Finasteride 1 mg is the FDA-approved dose for the treatment of male androgenetic alopecia (AGA — male pattern hair loss). Sold under the brand name Propecia (Merck) and widely available as generic finasteride 1 mg, it is taken as one 1 mg tablet once daily. The drug received FDA approval for AGA in December 1997 based on two pivotal 12-month, double-blind, placebo-controlled trials (Kaufman et al., 1998) plus a 5-year long-term extension study.

Key Dosage Facts

ParameterDetails
Approved dose1 mg orally once daily
AdministrationWith or without food
IndicationMale androgenetic alopecia (not approved for women)
Minimum duration before response assessment12 months of continuous daily use
Duration of treatmentIndefinite (benefit reverses within 6–12 months of stopping)
Brand namePropecia (Merck)
Generic availabilityYes — widely available; therapeutically equivalent
Approximate monthly cost (generic)$15–$35 (varies by pharmacy and insurance)
Approximate monthly cost (brand Propecia)$70–$120

Generic Finasteride vs. Propecia: Is Generic Equivalent?

Yes. Generic finasteride 1 mg has the same active ingredient, dose, and bioavailability as brand-name Propecia. The FDA requires generic manufacturers to demonstrate bioequivalence to the reference drug. For most men, switching from Propecia to generic finasteride produces no change in clinical effect. Saving $50–$100/month using generic is clinically well-supported.

What to Expect After Starting 1 mg

  • Months 1–3: No visible improvement; possible initial shedding; DHT suppression established by day 7
  • Months 3–6: Hair loss rate slows or stops in most responders
  • Months 6–12: Visible improvement in density and hair caliber for approximately 48–66% of men (by investigator assessment)
  • Months 12–24: Peak response; continued gradual improvement in some men
  • Long-term: Maintained benefit with continuous use; documented over 10 years (Rossi et al., 2011)

See the full finasteride results timeline.

Monitoring

  • Standardized photographs at baseline and 12 months — the most practical way to document progress
  • PSA baseline recommended before starting finasteride so future PSA values can be properly interpreted (finasteride reduces PSA ~50%)
  • No routine blood tests are required during finasteride 1 mg treatment in otherwise healthy men

Related: Finasteride 5 mg for BPH | Dosage hub | Results timeline

Sources

  • Kaufman KD, et al. “Finasteride in the treatment of men with androgenetic alopecia.” J Am Acad Dermatol. 1998;39(4):578–589.
  • Merck & Co. Propecia (finasteride 1 mg) US Prescribing Information. Revised 2022.