The use of PRP in the United States as part of Hair Transplantation does not require FDA approval, just as the use of blood transfusion during or after surgery does not require FDA approval. Use of PRP as part of the surgical treatment is defined as a procedure and is not subject to FDA regulations.

However:
In the United States, the device used to prepare PRP must have FDA approval. Centrifuges that separate PRP from whole blood for a medical purpose (e.g., to assist tissue healing) are medical devices covered by the Federal, Drug and Cosmetics Act. Federal law requires that manufacturers of medical devices must obtain clearance or approval for the products before offering them for sale. We use only FDA approved separation devices.

The FDA has not approved PRP as a medication specifically for use in hair transplantation. FDA approval would be based on objective evidence of efficacy (e.g. promoting healing, promoting hair growth) and safety.

The use of PRP specifically in hair transplantation to promote healing and hair growth could be considered when, for example:

Clinical trials of appropriate size and design are approved by the FDA, and
Results from the clinical trials convincingly demonstrate that the end-point goals or efficacy and safety have been met