Comparative Efficacy of Topical Chitosan and Minoxidil in Hair Loss: A Controlled Study With Microneedling.

BACKGROUND: Chitosan, a natural polysaccharide with immunomodulatory and regenerative properties, has shown promise in enhancing tissue repair. While 5% minoxidil remains the standard treatment for androgenetic alopecia, interest in non-hormonal or adjunctive therapies such as chitosan is growing. OBJECTIVE: To evaluate the clinical efficacy and safety of topical 2% chitosan applied after microneedling in comparison with 5% topical minoxidil and a no-treatment control group in patients with androgenetic alopecia or diffuse hair loss. METHODS: A prospective, controlled study enrolled 30 patients (aged 22-58 y), randomized equally into 3 groups (n=10 each): (1) microneedling followed by 4 mL of 2% chitosan (Chitosan group), (2) twice-daily application of 5% topical minoxidil (Minoxidil group), and (3) untreated control (Control group). Treatments continued for 6 months. Primary outcomes included trichoscopic hair density and hair shaft diameter; secondary outcomes included patient satisfaction scores and adverse events. A representative scalp biopsy from the chitosan group was evaluated histologically. RESULTS: After 6 months, both the chitosan and minoxidil groups demonstrated significant increases in mean hair density compared with the control group (+30.5% and +22.3%, respectively; P=0.032 and P=0.048). Although the chitosan group showed a numerically greater improvement than the minoxidil group, this difference was not statistically significant (P=0.62). Hair shaft diameter and patient satisfaction scores improved in both treatment groups. No meaningful changes were observed in the control group. Mild, transient erythema occurred in 3 patients (1 in the chitosan group and 2 in the minoxidil group). Histologic analysis in a chitosan-treated subject showed increased follicular density and improved dermal matrix organization. CONCLUSIONS: In this small controlled study, microneedling followed by topical 2% chitosan resulted in significant improvements in hair growth parameters compared with no treatment, and outcomes were generally comparable to those observed with 5% minoxidil. While these results are promising, the small sample size limits definitive conclusions regarding comparative efficacy. Larger, adequately powered trials are warranted to confirm these preliminary findings and to better delineate the role of chitosan as a standalone or adjunctive therapy. EVIDENCEBASED LEVEL: Level II.