Dutasteride (Dutasteride (Avodart))
A dual 5-alpha reductase inhibitor (type I and II) that blocks ~90% of DHT production, compared to finasteride's ~70%. Increasingly prescribed off-label for androgenetic alopecia when finasteride alone is insufficient.
How it works
Inhibits both type I and type II 5-alpha reductase isoenzymes, reducing serum DHT by ~90% and scalp DHT by ~50%. Prevents miniaturization of androgen-sensitive hair follicles in the vertex and frontal scalp.
Key facts
- Molecular weight: 528.53 Da
- Half-life: ~5 weeks (extremely long)
- Bioavailability: ~60% oral
- Storage: Room temperature. Do not handle if pregnant (teratogenic risk).
Dosing overview
- Typical dose: 0.5 mg
- Frequency: Daily
- Duration: 6-12 months minimum for visible results
- Route: Oral capsule
Reported benefits
- Superior DHT suppression vs finasteride
- Hair regrowth and thickening
- Reduced hair miniaturization
- Prostate volume reduction
- Effective for diffuse thinning
Possible side effects
- Sexual side effects (5-7%)
- Decreased libido
- Gynecomastia (rare)
- Depression (rare)
- Post-finasteride syndrome (controversial)
Research
- Dutasteride vs finasteride for AGA (2022): Dutasteride 0.5mg produced 12% greater hair count improvement than finasteride 1mg at 24 weeks in vertex AGA (Phase III).
- Long-term dutasteride safety for hair loss (2021): 5-year follow-up showed sustained hair maintenance in 90% of patients with sexual side effects occurring in <5% and resolving on discontinuation.
Compare Dutasteride
Community discussions about Dutasteride
- My First 6 Months on Dutasteride for Hair Loss – Thoughts? - 4 comments
- RU-58841 scalp irritation after 3 weeks, is this normal or am I reacting? - 4 comments
- Mixing KLOW with Dutasteride? Thoughts on timing and dosing? - 6 comments
- Ask the community about Dutasteride
Research and educational reference only. Not medical advice.