PRP (platelet-rich plasma) therapy for hair loss is a three-step medical treatment in which a person’s blood is drawn, processed, and then injected into the scalp.

Some in the medical community think that PRP injections trigger natural hair growth and maintain it by increasing blood supply to the hair follicle and increasing the thickness of the hair shaft. Sometimes this approach is combined with other hair loss procedures or medications. 

There hasn’t been enough research to prove if PRP is an effective hair loss treatment. However, PRP therapy has been in use since the 1980s. It’s been used for problems such as healing injured tendons, ligaments, and muscles.