Platelet-rich plasma (PRP) is a blood plasma preparation made from the patient’s own blood, which contains a large amount of platelets (thrombocytes). PRP is rich in various growth factors and other endogenous cell-stimulating substances and is used in modern medicine to stimulate healing and renewal processes.
PRP for hair loss?
In the case of non-scarring alopecia (androgenetic alopecia, alopecia areata, diffuse hair loss), PRP can activate hair follicles that are in the resting phase (it is assumed that the growth factors contained in the plasma preparation stimulate the follicle stem cells to divide).
A review article published in 2018 evaluated the results of twelve original studies on the use of PRP in androgenetic alopecia. The male and female subjects in the studies had received one or two to six PRP treatments at intervals of two weeks to three months, with a control group receiving a placebo treatment (with simple saline solution). Ten of these studies (and all studies with three or more PRP treatments) found a significant effect on hair density, hair diameter and subjective assessment of the hair situation by the subjects compared with placebo .
There are few publications on the use of PRP in alopecia areata that report good treatment success in individual cases  .
Some surgeons recommend their patients to undergo PRP treatment in the first few days after hair transplantation in order to give the transplanted follicles a particularly good start and accelerate wound healing .
Implementation of the PRP treatment
To obtain the platelet-rich plasma, 25 to 120 millilitres of blood are taken from you. Very soon after the separation of the remaining blood components, the plasma is injected at several points into the scalp, which has been made insensitive to pain by a local anaesthetic. Alternatively, PRP can be massaged into the scalp prepared by a microneedling application.