PRP is an autologous (comes from your blood) it is a preparation of platelets in concentrated plasma that contains a condensed platelet concentration. When platelet alpha granules become activated they release numerous growth factors, such as platelet derived growth factor, transforming growth factor, epidermal growth factor, and insulin like growth factor and other cytokines. These growth factors seem to stimulate cell proliferation and differentiation.
Once the blood is spun down and the PRP is removed it is activated just prior to placing it into the desired areas. Although the exact mechanisms are not known it is felt that the anagen or growth cycle is stimulated and prolonged.
PRP stimulates adult hair follicle stem cells deactivated by hair loss genes. This effectively reverses the hair follicle miniaturization process that eventually leads to thinning hair and baldness by reinvigorating dormant follicles and bathing them with PRP which is rich in growth factors and nutrients for stimulating hair growth. By this mechanism, PRPinjections stimulate hair growth and sustain viable native hairs longer. This means that you need to have some native hairs in the area of treatment in order for it to be successful. It will not work in a completely bald area or in areas of scars etc. We are not exactly sure on how frequently you will need the PRP injections currently we feel most people are having good results up to 6 month intervals. Many people require several months for the first treatment to manifest its effects.
There are several mechanisms to "activate" the factors in the PRP. When used in conjunction with surgery we have found that the "trauma" of creating incisions in the scalp stimulates the body to create those factors and when the PRP is injected or applied the bodies own natural process causes the PRP to begin its work. This is what the micro needling does. It brings your own factors to the area and then the concentrated PRP.
There are kits available that also contain those factors required to stimulate and activate the PRP. The micro needling or trauma method will create a little more redness and occasionally bruising than the nonautologous activation method. Either way there are some needles involved.