Platelet-Rich Plasma for Hair Loss: Update and Expert Q&A

According to estimates from the National Institutes of Health, androgenic alopecia affects 30 million women and 50 million men in the United States.¹ Oral finasteride and topical minoxidil comprise the currently approved non-surgical therapies for this condition. However, finasteride has been linked to undesirable adverse effects and is not indicated for female patients, and the long-term required daily use of minoxidil can become burdensome.²

These limitations underscore the need for additional treatment options for androgenic alopecia. Emerging research suggests that platelet-rich plasma (PRP) — an “autologous solution of plasma prepared from a patient’s own blood…. containing 4 to 7 times the baseline concentration of human platelets” — may be effective for this purpose.³ Some providers are already offering PRP in clinical practice and its popularity as a hair restoration therapy is growing.²

“The secretory α-granules within platelets release various growth factors…. [that] …induce tissue regeneration, collagen formation, re-epithelialization, and angiogenesis,” according to a 2018 review of PRP research.⁴ The investigators reported positive results for PRP as a treatment for androgenic alopecia, as have several other reviews and meta-analyses.^,6

A 2018 meta-analysis by Gupta, et al, focused on studies in which PRP was directly injected into the scalp of human patients and that used quantifiable measures of treatment success (in this case, hair density).² The final analysis, based on 4 studies with a pooled sample of 60 participants, revealed an overall standardized mean difference of 0.51 (95% CI, 0.14-0.88; I² = 0%) in favor of PRP compared with baseline.

In another meta-analysis published in the Journal of Cosmetic Dermatology in 2018, the investigators examined 6 studies (pooled N=177) describing quantitative outcomes of PRP vs controls in the treatment of androgenetic alopecia.⁷ Compared with the use of control treatments, PRP was associated with significant increases in hair number per cm² (mean difference [MD], 17.90; 95% CI; 5.84-29.95; P =.004) and hair cross-section thickness per 10⁻⁴ mm² (MD 0.22; 95% CI, 0.07-0.38; P =.005).

Across studies, PRP was linked to minimal adverse events and high patient satisfaction.²

The investigators in these papers emphasized the need for randomized controlled trials to further advance this practice. “New research will hopefully provide the data required to evaluate protocols for activation, additional beneficial components, and the minimum required frequency of treatments for effective results,” wrote Gupta, et al.²

To learn more about the use of PRP for hair restoration, Dermatology Advisor spoke with Jeffrey Rapaport, MD, FAAD, a New Jersey-based dermatologist in private practice who presented  a paper on the topic at the recent 2019 American Academy of Dermatology (AAD) annual meeting, and Raja Sivamani, MD, MS, CAP, adjunct associate professor of clinical dermatology and director of clinical research at the University of California, Davis, and medical editor at LearnSkin.com. Each doctor was also a co-investigator in  two of the papers cited here.3,

Dermatology Advisor: What does the research thus far suggest regarding PRP for hair restoration?