PRP, or platelet-rich plasma, is a hair loss treatment that uses a concentrated portion of your own blood to stimulate hair regrowth. A small blood sample is drawn, processed to isolate platelets at high concentration, then injected directly into thinning areas of your scalp. The platelets release growth factors that wake up dormant hair follicles and increase blood supply to the area, encouraging thicker, stronger hair over time.
How PRP Stimulates Hair Growth
Platelets are best known for clotting, but they also carry tiny packets called alpha granules loaded with growth factors. When injected into the scalp, these growth factors act on stem cells in the bulge area of hair follicles, which is the region responsible for generating new hair. They stimulate the development of new follicles and trigger the formation of new blood vessels around existing ones, improving the nutrient supply that hair needs to grow.
The key growth factors involved promote cell proliferation, blood vessel formation, and the survival of dermal papilla cells (the cells at the base of each follicle that control the hair growth cycle). In lab studies, dermal papilla cells showed ideal proliferation at a platelet concentration of about 1 to 1.5 million platelets per microliter, roughly four times or more the normal concentration found in whole blood. This concentration threshold matters because too few platelets won’t produce a meaningful effect, and clinics that prepare PRP properly aim for this range.
What the Procedure Looks Like
The process starts with a standard blood draw, typically around 30 to 60 milliliters from your arm. That sample goes into a centrifuge, a machine that spins the blood at high speed to separate it into layers. The platelet-rich layer is extracted and prepared for injection.
There are two main preparation methods. A single-spin technique is simpler and faster, producing good platelet recovery but retaining more white blood cells. A double-spin protocol adds a second centrifugation step to further concentrate platelets while reducing white blood cell content, which is generally preferred for skin and scalp applications because fewer white blood cells means less inflammation at the injection site. In practice, research comparing the two methods has found no significant difference in final platelet counts, though there’s a lot of variability depending on the specific centrifuge settings each clinic uses.
Once prepared, the PRP is injected into the scalp using a fine needle across the thinning areas. The whole appointment typically takes under an hour. Because the product comes from your own blood, the risk of an allergic or immune reaction is extremely low.
Treatment Schedule and Timeline
Most protocols follow a two-phase approach: an initial loading phase followed by ongoing maintenance.
The initial phase typically involves 3 to 4 treatments spaced about 4 to 6 weeks apart. This concentrated series builds up the growth factor signaling in your scalp and gives follicles repeated stimulation to shift from a resting phase into an active growth phase. Most people start noticing changes in hair texture and reduced shedding within the first couple of months, with more visible improvements in density and thickness emerging around 3 to 6 months after starting treatment.
After completing the initial series, maintenance sessions are recommended every 4 to 6 months to sustain the results. Without maintenance, the benefits gradually fade because PRP doesn’t permanently alter the follicle. It supports growth for as long as the signaling continues.
Recovery and Side Effects
One of the practical advantages of PRP is that there’s essentially no downtime. You can shower, shampoo, and condition your hair normally the same day. Most people return to their regular routine immediately after the appointment.
That said, minor side effects are common. You may experience some tenderness, redness, swelling, or bruising at the injection sites. Occasional headaches happen too. These typically resolve within a day or two. Because the treatment uses your own blood, more serious reactions are rare.
For the first 12 hours or so after treatment, it helps to avoid strenuous exercise and heavy lifting, since increased blood pressure can worsen bruising and scalp inflammation. You’ll also want to skip harsh hair products, avoid very hot showers, and minimize direct sun exposure on your scalp for the first few days to let the treatment settle without interference.
Who Benefits Most From PRP
PRP works best for people with early to moderate thinning, particularly androgenetic alopecia (the most common form of pattern hair loss in both men and women). It’s most effective when hair follicles are miniaturized but still alive. If an area of scalp has been completely bald for years, the follicles may be too far gone for PRP to revive them.
PRP is often used alongside other treatments like minoxidil or finasteride rather than as a standalone solution. Combining approaches tends to produce better results because each treatment targets hair loss through a different mechanism. Some people also use PRP after a hair transplant to improve graft survival and accelerate healing in the transplanted area.
Cost and Practical Considerations
PRP for hair loss is considered cosmetic and isn’t covered by insurance. Individual sessions typically range from $500 to $1,500 depending on the clinic, the preparation method, and your geographic area. When you factor in 3 to 4 initial sessions plus maintenance every few months, the annual cost adds up quickly.
Results vary. Some people see meaningful improvement in hair density and thickness, while others notice only modest changes. Response depends on factors like the severity of hair loss, age, the quality of the PRP preparation, and the specific injection technique. There’s no standardized protocol across the industry yet, which means the experience and results can differ significantly from one provider to another. Clinics that measure and verify their platelet concentrations before injection tend to produce more consistent outcomes than those using a one-size-fits-all approach.