Update: Based on a reader’s comment to this post regarding frequency of treatment, I contacted Dr. Greco and he said that he tries to get his hair transplant patients to get PRP injections once a year after the transplant. He uses a more purified version of PRP called CRP, and the details of that can be found on his website.

Greco Medical has been a long-time proponent of using platelet-rich plasma (PRP) during hair restoration procedures. In September 2014, The Journal of Dermatologic Surgery in the US published the largest ever PRP study related to hair. Dr. Joseph Greco was one of the four authors of this study.

I am impressed by some of the detailed content on there and they had both male (42) and female (22) participants. It does seem a bit limiting in that only “two independent evaluators” decided on the success or failure of the end results. The two before and after photos in there (female on page 1015, and male on page 1016) are impressive and in all likelihood among the best-case results.

According to the two evaluators, the overall proportion of patients seeing a clinically significant improvement at 6 months post PRP treatment was 40.6% and 54.7%, respectively.

As with low-level laser therapy (LLLT), I have also always been very skeptical about PRP. My skepticism for both has subsided in the past year or two as more supportive studies have come out and as more surgeons have started offering both LLLT and PRP. However, I am still not convinced that either of these technologies offers more than a limited improvement in hair quality and thickness for the average person.

It also does not help when most of these study authors include hair transplant surgeons who are already big proponents of PRP and/or LLLT in their practices. It would be far more believable if researchers, universities and companies that are entirely financially disassociated with PRP published such studies.