Additive Effects of Platelet-Rich Plasma and Systemic Therapies in Androgenetic Alopecia: A Retrospective Study

Introduction: Established treatments for androgenetic alopecia (AGA) include low-dose oral minoxidil (LDOM), spironolactone, finasteride, dutasteride, and platelet-rich plasma (PRP). While PRP is often combined with topical minoxidil, studies on its use with systemic agents are limited. This study compares trichometric outcomes and side effects between PRP monotherapy and PRP plus systemic therapy. Methods: An IRB-approved retrospective review was conducted of NYU AGA patients treated between 11/1/17-8/1/25. Changes in hair density (hairs/cm²) and width (µm) were assessed from baseline to final follow-up among patients receiving PRP alone or PRP with LDOM, spironolactone, finasteride, or dutasteride. AGA severity was determined via Hamilton-Norwood or Ludwig scale. Mann-Whitney U tests, Fisher exact tests, and multivariate linear regression were performed. Results: Fifty-five patients met inclusion criteria (65.5% female, mean age 49). Compared to monotherapy (n=6), combination therapy (n=49) showed greater, though not statistically significant, gains in density (+6.06 hairs/cm², p=0.703) and width (+3.59 µm, p=0.460). Controlling for treatment type, moderate AGA predicted significantly greater density improvement (+25.11 hairs/cm², p=0.040). Conclusions: Combination therapy showed numerically higher but statistically non-significant improvements without increased adverse effects. These findings support further prospective studies to optimize combination regimens and patient selection by AGA severity.