What is the comparison between oral minoxidil and oral finasteride (Propecia) for treating hair loss?

Oral Minoxidil vs. Oral Finasteride for Hair Loss

Oral minoxidil is more effective than oral finasteride for treating androgenetic alopecia, with dutasteride showing the highest efficacy among these options. 1

Comparative Efficacy

• Efficacy ranking in decreasing order: dutasteride 0.5 mg/day > finasteride 5 mg/day > minoxidil 5 mg/day > finasteride 1 mg/day > minoxidil 0.25 mg/day 1
• Oral finasteride 1 mg/day shows efficacy in arresting hair loss in more than 80% of patients after 12 months of treatment 2
• In a comparative study, oral finasteride demonstrated higher clinical cure rates (80%) compared to topical minoxidil (52%) 3
• Complex therapy combining PRP with minoxidil is more effective than minoxidil monotherapy for treating androgenetic alopecia 4

Mechanism of Action

• Minoxidil acts through multiple pathways to promote hair growth:

  • Functions as a vasodilator
  • Has anti-inflammatory properties
  • Induces Wnt/β-catenin signaling
  • Shows some antiandrogen activity 1

• Finasteride works by:

  • Inhibiting 5α-reductase type II isoenzyme
  • Blocking conversion of testosterone to dihydrotestosterone (DHT), the androgen responsible for male pattern hair loss 5
  • Reducing both scalp and plasma DHT levels 6

Side Effect Profiles

• Oral minoxidil side effects:

  • Predominantly causes hypertrichosis (excessive hair growth in unwanted areas)
  • Cardiovascular symptoms in a dose-dependent manner 1

• Oral finasteride side effects:

  • Sexual dysfunction (3.8% vs 2.1% in placebo) including decreased libido, ejaculation disorder, and erectile dysfunction 5
  • Neuropsychiatric side effects 1
  • All sexual adverse events reversed upon discontinuation of therapy 5

• Topical finasteride may be an alternative for those concerned about systemic side effects of oral finasteride, with side effects limited to application site reactions 6

Duration of Effect and Pharmacokinetics

• The average plasma half-lives differ significantly:

  • Minoxidil: ~4 hours
  • Finasteride: ~4.5 hours
  • Dutasteride: ~5 weeks 1

• Evidence suggests that improvement in hair count with finasteride reported after 1 year is maintained during 2 years of treatment 5

Clinical Considerations and Pitfalls

• Oral finasteride is contraindicated in pregnant women due to risk of hypospadias in male fetuses 5
• The American Urological Association suggests finasteride may be ineffective in patients without enlarged prostates, which could impact its efficacy in different populations with androgenetic alopecia 7
• Topical finasteride (not FDA-approved) may provide similar efficacy to oral finasteride with reduced systemic side effects 6
• Combination therapies often yield better results than monotherapy, with PRP combined with minoxidil showing superior outcomes for hair density and thickness 4

Treatment Algorithm

1. For maximum efficacy with higher risk of side effects: Consider oral minoxidil 5 mg/day 1
2. For balanced efficacy and safety profile: Use oral finasteride 1 mg/day (FDA-approved for male pattern hair loss) 5
3. For those concerned about systemic side effects: Consider topical finasteride as an alternative 6
4. For optimal results: Combination therapy with PRP and minoxidil may provide enhanced efficacy 4