PRP May Offer the Strongest Hair Transplant Evidence

Structured review highlights stronger evidence for platelet-rich plasma than for exosome-based and other emerging regenerative therapies while underscoring the need for standardized transplantation-specific research.

By
Andrea Surnit
July 17, 2026
4 min

MDSpire News

Objective:

To evaluate the effectiveness of regenerative therapies for hair loss and hair transplantation, focusing on platelet-rich plasma (PRP) and other emerging approaches.

Approach:

Study Design: Structured narrative review of English-language studies from PubMed/MEDLINE, Scopus, and Google Scholar through February 2025.
Eligibility Criteria: Included randomized controlled trials, prospective and retrospective clinical studies, systematic reviews, meta-analyses, and translational preclinical studies.
Outcome Measures: Assessed hair density, hair shaft diameter, graft survival, hair yield, wound healing, time to visible regrowth, shock loss, and patient-reported satisfaction.

Key Findings:

PRP had the most mature evidence base among reviewed therapies.
Randomized trials reported increases in hair density of approximately 10 to 30 hairs/cm² with PRP.
Evidence specific to hair transplantation was limited and inconsistent.
Exosome-based therapies had considerably less developed evidence, with no robust randomized trials.
Low-level laser therapy showed moderate evidence for androgenetic alopecia, but transplantation-specific data was limited.

Interpretation:

PRP is currently the best-supported regenerative adjunct in hair transplantation, but higher-quality studies are needed for broader clinical application.