Overview
Dr. Gary Linkov compares finasteride and dutasteride for hair loss treatment, outlining their efficacy, side effects, practical use, and his clinical approach. He emphasizes starting conservatively with finasteride before considering dutasteride for most patients.
Mechanisms and Efficacy
- Finasteride inhibits type 2 five alpha reductase, reducing DHT by about 70%.
- Dutasteride inhibits both type 1 and type 2 five alpha reductase, reducing DHT by 90–98%.
- A 2024 systematic review found dutasteride superior to finasteride in hair count, photographic assessment, and self-assessment.
- Most randomized trials of dutasteride for hair loss are limited to 24 weeks; longer-term data are lacking.
Side Effect Profiles
- Finasteride’s erectile dysfunction incidence: 1.3–2%; decreased libido: 1.8–2.6%.
- Dutasteride’s erectile dysfunction incidence: 4–6%; decreased libido: 3–4%.
- Side effects are mostly reversible and tend to decrease over time.
- Dutasteride’s longer half-life makes side effects slower to resolve after discontinuation.
- Dose adjustments are easier with finasteride due to its shorter half-life.
Practical Usage & Clinical Approach
- Finasteride is FDA-approved for male pattern hair loss at 1mg/day.
- Dutasteride is FDA-approved for BPH (0.5mg/day) but not for hair loss in the US (approved for hair loss in Japan, South Korea, Taiwan).
- Dr. Linkov starts patients on finasteride for at least 3 months; only switches to dutasteride (0.5mg/day) if needed.
- Patients switching from finasteride to dutasteride rarely experience new side effects in his practice.
- Topical or injected dutasteride lacks robust clinical trial evidence, so is not routinely offered.
- Other treatments (minoxidil, laser therapy, PRP, nutrition) can supplement medications.
Hair Transplantation Considerations
- Transplants have limited donor supply; medical therapy is essential for stabilizing existing hair.
- Transplanted hair can still be DHT sensitive and may require ongoing medical therapy for maintenance.
- Medications and surgery are synergistic for reliable, lasting results.
Common Patient Questions
- Switching back from dutasteride to finasteride is possible but seldom necessary.
- 0.5mg/day dutasteride suffices for most men; higher doses may increase side effect risk.
- Topical or injected dutasteride lacks sufficient data for broad recommendation.
Decisions
- Start hair loss patients on finasteride before considering dutasteride.
- Avoid initial dutasteride therapy due to higher risk of side effects and difficulty in dose adjustment.
Recommendations / Advice
- Medical therapy should precede and accompany transplant surgery to maximize outcomes.
- Begin treatment early, as hair loss progresses with inaction.
- Balance medication efficacy with potential side effects before escalating treatment.
Questions / Follow-Ups
- Larger and longer clinical trials needed for oral, topical, and injected dutasteride in hair loss.
- Ongoing assessment required for patients not responding to finasteride.