PRP for Hair Restoration

When it comes to hair restoration options, there are plenty of choices available to the general public.  One of the more mysterious methods of hair restoration is the use of PRP (platelet-rich plasma) to stimulate hair growth.  The mysterious portion of the treatment comes from the lack of solid evidence regarding the effectiveness of the treatment.


The interesting thing about PRP treatment for hair restoration is that nobody is really sure that it does work. The more important point is that the theory behind it may work. To date, nobody has really proven that it does work. There are a lot of people out there doing PRP, but it is a very difficult area to study because what every doctor does for PRP is different.

In other words, the PRP that is manufactured in Rome is manufactured in a different system from Houston or Cleveland or Minnesota. There ends up being multiple types of platelet-rich plasma out there and nobody has done a consistent study to look at which one works the best. There also is not anybody doing anything out there to even prove against the placebo that what they have done is real. In other words, there is a lot of hype and a lot of talk, but the reality is there is very little science.

That being said, is there reason to think that it might work? The answer to that question is “yes”. Over the last 15 or 20 years, there have been attempts to try and tissue culture hair follicle stem cells to get the stem cell to multiply and culture, and then give them back to the patient to grow more hair. In the process of doing that, it has been discovered that the hair follicle growth cycle is controlled by maybe six or seven different cytokines, or growth factors. These are chemicals that facilitate the communication between cells and the hair follicle. They are the chemicals that are responsible for turning on the hair follicle to grow and turning off the hair follicle to go into the resting phase. At any given time, only 85% of the hair on the head is actively growing. The other 15% is in a resting phase that does not grow.  The active growing phase lasts for about seven or eight years. The resting phase lasts for about 18 months to two years and then the resting hair follicle turns on and starts to grow again.

Similar to Wound Healing

It has been noticed that the cytokines and growth factors that function in wound healing are very similar to the cytokines that function in hair cycling. That makes a huge amount of sense because most of wound healing comes from the hair follicle stem cells. For example, if there is a first degree burn then the wound heals very quickly (like sunburn). With a second degree burn, the hair follicles are less intact because it is just the upper layer of skin that has been burned and those wounds heal very quickly with no scar. But a third degree burn has a terrible delay in getting the wound to heal because the hair follicles themselves have been destroyed.

What has been learned in wound healing literature over the last 10 or 15 years is that platelets not only function in phase one of wound healing to keep the patient from bleeding to death, but they also return. Additional platelets return to the wound many times over the first year or two of healing and provide additional cytokines and self-communication to soften the wound, shrink the scar, make the scar the right color, and fade the color of the scar. So platelets are active in wound healing probably for a whole year and not just for the first couple of hours after the injury as believed years ago.

How does this relate to PRP for hair restoration? It turns out that platelets are highly concentrated with all the growth factors that it takes to drive the hair cycle. The growth factors are the same. The wound healing growth factors that are carried by platelets are also the same hair cycling chemicals that are required to turn the hair on and off.  If this theory is true, it is not going to add hair. It is just going to turn on the sleeping hair. It will function like finasteride or Rogaine and turn on the hair. It is not going to stimulate hair, it will just turn on the stem cells.

Test Study

There is a theory in which people are playing with platelet-rich plasma and are thinking that the PRP for hair restoration technique will probably grow hair. The problem is there has been only one double blind placebo controlled study looking at platelet function in hair growth. The study has not been published yet. It was a pilot (small) study of PRP injections in women with proven female pattern hair loss with a total of 28 patients in the study.

About half the patients were in placebo and half the patients were in real PRP. The study did not demonstrate any significant difference between the women that were in placebo and the women that were in PRP. What the study did discover is that both patient groups had patients with an increased amount of hair growth and patients that thought they got better. There was no statistical difference between the study group and the placebo group. About 10% or 12% of the patients thought they got better, and it did get better when their hair counts and their hair masses were measured.

It might be a result of the needling or the minor trauma to the scalp done by the injections. Needling the scalp might bring enough of the patients own PRP into the area to get a hair response in a small number of patients. It could just be the placebo effect or it might be a real PRP effect. Remember that anytime a person is wounded, their body responds by throwing PRP at the injury. It may just be that all that has to be done is needle the scalp to get a positive response. The problem is the people that are really pushing this have never studied it against the placebo. They have just been making observations. The polite thing to say is the data is very soft on whether PRP actually grows hair or not.

Manufacturing Options

There are a variety of systems available to manufacture PRP for hair restoration. Some of the systems include the Angel system, Harvest, and AutoloGel. Each of these systems can manufacture two or three kinds of PRP. These are three separate systems that are in the U.S. and there are probably two or three more.

A lot of people that do PRP just put the blood in a centrifuge, spin it down, pipe off the PRP, and then spin it a second time. There is about 10 or 20 different ways to manufacture PRP. For example, the Angel system can spin the PRP so that it gets a PRP that only has 2% hematocrit. That means that 2% of the PRP is going to have red blood cells in it. Or, a doctor can spin it with as much as 6% or 8% hematocrit. That is another big question out there. Does PRP work better if a doctor spins it with a higher hematocrit? Nobody has compared them so nobody knows. There are a lot of questions that are unanswered. There is a lot of science that says “yes” this may work. There is no evidence that it really grows hair. What is out there is a lot of rumors and speculation and many doctors performing the procedure, but nobody has looked at it critically.


The cost for PRP for hair restoration varies from doctor to doctor in the United States. The cost to manufacture the PRP runs around $450-$600. Many doctors are charging two to three times that for the treatment. The cost for selling three treatments can be as much as $2,500.

Final Thoughts

While it is known that there are six or seven cytokines and growth factors that turn hair follicles on and off, there might actually be more than that. So there may be other things besides what is in the PRP that needs to be present to turn it on and off. The fact that it does not work in everybody is an implication that nobody has all the answers to yet. PRP hair treatment for hair restoration is not going to be the fantasy that people would like it to be. If a patient decides to undergo a PRP treatment, they need to proceed with realistic expectations of what the treatment is capable of accomplishing when it comes to hair restoration.