Platelet-Rich Plasma (PRP) is an increasingly popular treatment in the field of regenerative medicine including as treatment for hair loss.
What is PRP?
Platelet rich plasma is a product of our own blood which exploits our innate ability to regenerate tissues when we are injured. To prepare PRP, a small volume of blood is taken from a vein in the arm like when you undergo a routine blood analysis. It is then centrifuged to separate and stratify the blood components and processed according to the protocol followed by the clinic. After processing, the PRP obtained through this operation is injected with a syringe and a tiny needle in the area affected by hair loss.
PRP contains dozens of growth factors and thousands other bioactive molecules that stimulate tissue regeneration and healing by:
- increasing blood flow through angiogenesis (building new blood vessels) which in turn will bring more oxygen and nutrients,
- recruiting stem cells to the treated area,
- stimulating in general cell migration, proliferation, growth and differentiation.
For a more in-depth look at what PRP is you can check my article dedicated to it.
How does PRP for hair loss work?
PRP stimulates the stem cells in the hair follicle (more precisely in the follicular bulge): by telling them to proliferate it causes an increased development of new follicles. Moreover, platelet rich plasma pushes hair follicles to the anagen phase which is the one of active growth of the hair; some of the growth factors also inhibit apoptosis (the “programmed cell death”) and stimulate the development of new blood vessels which will lead to more oxygen and nutrients delivered to the scalp and to the hair follicles.
How many PRP treatments are necessary to treat hair loss?
In most studies on PRP and hair loss, the treatment was performed 3 to 6 times at 2 to 6 weeks intervals; those who respond to the treatment should repeat the injections at 3-6 months intervals in order to maintain the results. Those who do not respond to the treatment may also be advised to repeat the first treatment cycle: this is because of the very low risk of adverse events making it worth a shot to repeat treatment until there is evidence of hair regrowth.
A recent meta-analysis positively correlates the frequency of the treatments with larger increases in hair density, meaning the more treatments per month the better the results with 4+ treatments per month yielding the best results; due to the controversies surrounding the journal this study was published in, this correlation requires further evidence before being considered truthful.
Is platelet rich plasma effective in treating alopecia?
According to several research papers, meta-analysis and systematic reviews, PRP seems to be effective in treating hair loss by
- increasing hair density (number of hairs per square centimeter of scalp)
- increasing terminal hair density (the thick and fully developed hair per cm2)
- increasing number of hairs in the active growth (anagen) phase
- increasing hair thickness/cross section
- increasing the number of hair follicles
- increasing the number of blood vessels around hair follicles
- increasing the strength of the hair on the scalp, measured with a “pull test”
- inhibiting cell apoptosis (programmed cell death)
It was also noted in several studies that PRP increased skin thickness, fibroblast proliferation, and number of collagen fibers.
PRP for hair loss “controversies”
While there is an increasing body of evidence showing the effectiveness of PRP in treating hair loss and other conditions, platelet rich plasma is not yet considered 100% effective and is not yet one the FDA-approved treatments for hair loss or other ailments.
The reason for this is that some of the studies, for example, lack a control group making them low quality. Other studies don’t look at objective and accurate evaluation methods but rely on subjective parameters. The number of subjects in each study is often small and the PRP preparation method varies widely and tends to be different in each study.
While there are dozens of studies available showing improvement and effectiveness in treating hair loss, there are also a few studies that show no improvements in the parameters analyzed.
In order to say that PRP is non-disputably an effective treatment we need a standardized preparation and treatment protocol and better-quality studies analyzing objective parameters and with a large pool of subjects.
Older people, those with a lower platelet count and those with other medical conditions or not following a healthy lifestyle may also not benefit, or benefit less, from PRP treatment due to the lower concentration of bioactive molecules and lower potential for tissue regeneration of the platelet rich plasma derived from their own blood.
How to prepare before PRP treatment for hair loss
Patients are advised to be well hydrated on the day of the PRP treatment. The week before, you should eat a healthy diet, avoid alcohol, tobacco or drugs, have regular and healthy sleep patterns, exercise and avoid stress: your lifestyle can influence the composition of your blood and you may want to optimize its potential.
You will also likely be advised to avoid NSAIDs for the week prior to the treatment (see next paragraph). Ask your doctor for advice tailored to your case.
What NOT to do after PRP for hair loss
After the treatment, you should keep following the healthy lifestyle described in the previous chapter to aid your organism in the healing and regenerative processes.
You should also avoid NSAIDs as they may inhibit platelet function and decrease the efficacy of the treatment; while a study from the cardiac surgery literature suggests no difference in growth factors release between patients taking aspirin or clopidogrel and those who don’t, more data is needed to say that they are safe to take prior and after the PRP injections and that they won’t compromise the efficacy of the treatment specifically while doing PRP for the treatment of hair loss.
Always refer to your treating physician for advice on what not to do after PRP injections.
Complications of platelet rich plasma for hair loss
Unlike other widely used treatments for hair loss like finasteride, dutasteride and minoxidil, PRP is generally safe and with few, mild and transient side effects that subside without treatment in a couple of days. The most widely reported complications are pain at the injection site and bleeding, while less commonly post-treatment tenderness, swelling, itching and desquamation were reported as well.
PRP is in general considered a very safe treatment being an autologous material, meaning it’s derived from our own bodies, with very low risks and side effects.
- Hair Transplant Surgery and Platelet Rich Plasma – Evidence-Based Essentials
LN Lee – Springer, 2020
- Platelet-Rich Plasma for Treating Androgenic Alopecia: A Systematic Review.
GY Mao – Aesthetic Plastic Surgery, Oct 2019
- Platelet-Rich Plasma for Hair Loss: Review of Methods and Results.
KW Badran – Facial Plastic Surgery Clinics of North America, Nov 2018
- Platelet-Rich Plasma as a Treatment for Androgenetic Alopecia.
AK Gupta – Dermatologic Surgery, Oct 2019
- Effectiveness of Platelet-Rich Plasma Therapy in Androgenic Alopecia-A Meta-Analysis.
SR Georgescu – Journal of Personalized Medicine, Feb 2022