Finasteride Long-Term Safety: The 10-Year Study
Medically reviewed by [Reviewer Name, MD] | Last reviewed: August 2026 | Editorial policy
Rossi et al. (2011; Dermatologic Therapy) conducted a 10-year prospective follow-up of 118 men with AGA treated with finasteride 1 mg daily. This represents the longest-duration published prospective study of finasteride 1 mg for AGA, providing important data on long-term maintenance of efficacy and safety.
Study Design
| Parameter | Details |
|---|---|
| Design | Prospective cohort; non-randomized (all participants treated with finasteride 1 mg) |
| Population | 118 men with AGA, age 20 to 61 |
| Duration | 10 years of continuous finasteride 1 mg/day |
| Outcome measures | Photographic standardized hair assessment; investigator rating; adverse event monitoring |
Key Results
- Efficacy was not reduced over time; in 21% of cases, continuing beyond 5 years gave better results
- 42.8% of men aged 20 to 30 had not improved even after 10 years; men over 30 improved more
- Adverse events were consistent with short-term data; no new safety signals emerged at 10 years
- Sexual adverse effects remained within the range documented in 1-year trials; no cumulative worsening over time
Limitations
- Non-randomized; no placebo control at 10 years
- Single-center; relatively small sample (n=118)
- Survival bias: men who continued treatment for 10 years may represent a self-selected group of tolerators/responders
This study remains the most important long-term safety/efficacy data point for finasteride 1 mg and is widely cited as evidence that long-term use does not produce cumulative harm. See: Results timeline
Sources
- Rossi A, et al. “Finasteride, 1 mg daily administration on male androgenetic alopecia in different age groups: 10-year follow-up.” Dermatol Ther. 2011;24(4):455-461.