Melatonin and the Human Hair Follicle: 2023 Review Research Summary
This is a plain-language summary of the original published research. We do not add conclusions or opinions of our own. This is not medical advice — consult a certified healthcare practitioner before making any decision.
Original research published in Journal of Drugs in Dermatology, 2023
Melatonin and the Human Hair Follicle
Study conclusion
Review of 11 human studies involving 2,267 patients found that 8 of 11 studies reported positive outcomes after topical melatonin for pattern hair loss. The apparent effective dose was 0.0033% or 0.1% once daily for 90–180 days. Most studies were not double-blind placebo-controlled; only one double-blind RCT exists.
Strength of evidence
This was a systematic review covering 11 human studies. The score is limited because only one of the 11 studies was a double-blind placebo-controlled RCT (Fischer 2004, n=40). Most others were open-label or observational. The overall evidence quality is low.
Who it applies to
Who was studied
Adults with pattern hair loss or other types of alopecia. 2,267 patients across 11 studies. Topical melatonin applied to the scalp at various concentrations.
Who was NOT studied
Men in double-blind placebo-controlled conditions — the only double-blind RCT studied women only.
What to look for when shopping
Topical melatonin is available in some scalp products. No topical melatonin product is FDA-approved for hair loss. Evidence quality is low and mostly from open-label studies.
What research cannot help you decide
Whether topical melatonin works in a large rigorous placebo-controlled trial. How it compares to minoxidil. Whether the 0.1% concentration is optimal.
Key findings
- 8 of 11 human studies reported positive outcomes after topical melatonin for hair loss
- The apparent effective dose across studies was 0.0033% or 0.1% applied once daily for 90–180 days
- Most of the 11 included studies were open-label or observational — not double-blind placebo-controlled
- Only one double-blind placebo-controlled RCT exists (Fischer 2004, n=40 women)
- No topical melatonin product is FDA-approved for hair loss
What they did
Researchers reviewed all published human studies of topical melatonin for hair loss. 11 studies covering 2,267 patients were identified. Study designs included RCTs, open-label studies, and observational studies. Outcomes, concentrations, and durations were reviewed narratively.
What they found
| Comparison | Result | Significant? |
|---|---|---|
| Topical melatonin — positive outcomes across 11 studies | 8 of 11 studies reported positive outcomes | No |
| Apparent effective dose — based on review | 0.0033% or 0.1% once daily for 90–180 days | No |
| Double-blind placebo-controlled RCT evidence | Only one exists — Fischer 2004, n=40 women | No |
What this study does not show
- 1.Whether topical melatonin works in a large well-powered double-blind trial.
- 2.How topical melatonin compares to minoxidil.
- 3.Whether results apply equally to men — the only double-blind RCT studied women only.
Limitations
- 1.Only 1 double-blind placebo-controlled RCT exists
- 2.Most included studies were open-label or observational
- 3.Evidence quality was low across most included studies
- 4.No topical melatonin product is FDA-approved for hair loss
- 5.Seasonal effects were not controlled in studies without placebo arms
Who funded it
No funding source declared. No conflicts of interest reported.
Used in these articles
Links added as fact-checks and articles citing this study are published.