The importance of dual 5alpha-reductase inhibition in the treatment of male pattern hair loss: results of a randomized placebo-controlled study of dutasteride versus finasteride.
Level 2 - randomized trial
Randomized controlled trial evaluating multiple doses of dutasteride versus finasteride and placebo.
PubMed 17110217 · doi:10.1016/j.jaad.2006.05.007
What was done
A total of 416 men aged 21 to 45 years with male pattern hair loss were randomized to receive daily oral doses of dutasteride (0.05, 0.1, 0.5, or 2.5 mg), finasteride (5 mg), or placebo for 24 weeks. The study evaluated target area hair counts, expert panel photographic assessments, investigator global evaluations, and changes in scalp and serum dihydrotestosterone and testosterone levels.
What was found
Dutasteride increased target area hair count versus placebo in a dose-dependent manner. Dutasteride 2.5 mg was superior to finasteride 5 mg at both 12 and 24 weeks, with findings corroborated by expert photographic review and investigator assessment. Dutasteride produced dose-dependent decreases in scalp and serum dihydrotestosterone alongside dose-dependent increases in testosterone. The abstract reports these directions and relative findings but provides no numerical values, effect sizes, or p-values.
Why it matters
This trial demonstrates that dual 5alpha-reductase inhibition with dutasteride can enhance scalp hair regrowth in male pattern hair loss beyond the efficacy achieved by finasteride over a 24-week period.
Limits
The study duration was restricted to 24 weeks, precluding conclusions about long-term efficacy or durability. The abstract reports no numerical values, variances, or statistical test metrics. Adverse events and safety profiles are completely omitted from the abstract. Finasteride was dosed at 5 mg rather than the standard 1 mg dose typically approved for alopecia.
Cited by
- context Dutasteride at dosages up to 2.5 mg daily has been used for benign prostatic hyperplasia with a low prevalence of side effects.