H
Add Listing

Finasteride (Propecia)

A·Strong Evidence

FDA-approved prescription pill for male pattern baldness. Blocks DHT to slow hair loss and promote regrowth.

DS

Written by

Dr. Sarah Mitchell, MD

Board-Certified Dermatologist

Last updated: January 28, 2026

View author profile

Overview

Finasteride (brand name Propecia) is an oral medication FDA-approved for treating male pattern hair loss (androgenetic alopecia). First approved in 1997, it has become one of the most widely prescribed treatments for hair loss in men.

Unlike topical treatments like minoxidil, finasteride works systemically by blocking the conversion of testosterone into dihydrotestosterone (DHT), the hormone primarily responsible for male pattern baldness.

Quick Facts

  • • Type: Prescription oral medication (pill)
  • • Dosage: 1mg once daily
  • • FDA Approved: Yes, for men only
  • • Evidence Grade: A (Strong evidence from multiple RCTs)
  • • Generic Available: Yes (significantly cheaper)

How It Works

Finasteride is a 5-alpha-reductase inhibitor. Here's what that means:

  1. Blocks DHT Production: The enzyme 5-alpha-reductase converts testosterone into DHT. Finasteride blocks this enzyme, reducing DHT levels in the scalp by up to 60-70%.
  2. Protects Hair Follicles: DHT causes hair follicles to shrink (miniaturize) over time. By reducing DHT, finasteride prevents further miniaturization and allows some follicles to recover.
  3. Stops Hair Loss Progression: Most men see slowed or stopped hair loss. Some experience regrowth, particularly on the crown.

Type II vs Type I 5-Alpha-Reductase

Finasteride primarily blocks the Type II enzyme found in hair follicles and prostate. Dutasteride blocks both Type I and II, which is why it's more potent but has more side effects.

Evidence Summary

A·Strong Evidence

Grade A: Strong Evidence

Multiple large, high-quality randomized controlled trials over 20+ years. Consistent results across studies. FDA-approved based on extensive clinical data.

Finasteride has been studied extensively in thousands of men:

  • 5-year study (1998): 65% of men maintained or increased hair count vs. 35% on placebo
  • Long-term data (10+ years): Continued effectiveness with ongoing use
  • Crown vs. hairline: More effective on crown; modest improvement on frontal hairline
  • Age factor: More effective in younger men (under 40) with recent hair loss

Effectiveness

65-90%

Stop or slow hair loss

40-50%

Experience regrowth

3-6 mo

Time to see results

What to Expect:

  • Best Results: Younger men (20-40) with recent hair loss on the crown
  • Maintenance: Most men successfully stop progression
  • Regrowth: Variable; don't expect dramatic transformation
  • Won't Work: Completely bald areas (no follicles left to save)

Usage & Dosage

Standard Dosage

• Dose: 1mg once daily

• Timing: Take at the same time each day (food doesn't matter)

• Prescription Required: Yes (doctor or telemedicine)

• Duration: Ongoing — must continue to maintain results

Important Notes

  • Consistency matters: Take daily; missing doses reduces effectiveness
  • Be patient: Takes 3-6 months to see results; full effect at 12 months
  • Initial shedding: Some men experience temporary shedding in first 2-3 months (normal — this is follicles resetting)
  • If you stop: Hair loss resumes within 6-12 months

Side Effects & Safety

Common Side Effects (2-5% of users)

  • • Decreased libido
  • • Erectile dysfunction
  • • Reduced ejaculate volume

Note: These side effects usually occur in the first year and often improve with continued use.

Less Common Side Effects

  • • Breast tenderness or enlargement (gynecomastia) — rare
  • • Depression or mood changes — controversial, needs more research
  • • Allergic reactions — very rare

⚠️ Important Warnings

  • • Women: NOT approved for women. Can cause birth defects — pregnant women should not touch crushed tablets
  • • Post-Finasteride Syndrome: Rare reports of persistent side effects after stopping. Controversial and not fully understood.
  • • PSA Levels: Finasteride lowers PSA (prostate marker); inform your doctor before PSA testing
  • • Blood Donation: Wait 1 month after stopping before donating blood

Who It's For / Who Should Avoid

Good Candidate:

  • ✓ Men with male pattern baldness
  • ✓ Age 18-60 (most effective under 40)
  • ✓ Recent hair loss (within 5 years)
  • ✓ Thinning crown or mid-scalp
  • ✓ Committed to daily pill
  • ✓ Realistic expectations

Should Avoid:

  • ✗ Women (especially pregnant/planning pregnancy)
  • ✗ Complete baldness (no follicles to save)
  • ✗ Patchy hair loss (likely not male pattern baldness)
  • ✗ History of depression or sexual dysfunction
  • ✗ Liver disease
  • ✗ Under age 18

Cost Considerations

Generic Finasteride

$20-40

Per month

GoodRx, telemedicine services

Brand (Propecia)

$70-80

Per month

Traditional pharmacy

Doctor Visit

$0-200

Initial + Annual

Telemedicine cheaper

Ways to Save:

  • Use generic finasteride (identical to brand)
  • Online telemedicine services (e.g., Hims, Keeps) — often $20-30/month all-in
  • GoodRx coupons at traditional pharmacies
  • 3-month or 6-month supplies (small discount)
  • Some insurance covers it (uncommon for hair loss)

References

  1. 1.
    Kaufman KD, Olsen EA, Whiting D, et al. "Finasteride in the treatment of men with androgenetic alopecia." J Am Acad Dermatol, 1998. DOI: 10.1016/s0190-9622(98)70007-6
  2. 2.
    Rossi A, Cantisani C, Melis L, Iorio A, Scali E, Calvieri S. "Finasteride, 1 mg daily administration on male androgenetic alopecia in different age groups." Dermatol Ther, 2011. DOI: 10.1111/j.1529-8019.2011.01415.x
Ready to try Finasteride?
Find a DermatologistOr: Compare: Finasteride vs Minoxidil