PRP (platelet-rich plasma) treatment is a medical procedure that uses a concentrated portion of your own blood to accelerate healing in damaged tissues. A small blood sample is drawn, spun in a centrifuge to separate out the platelets, and then injected into the injured area. The resulting preparation contains three to five times more platelets than normal blood, flooding the treatment site with the body’s natural healing signals.
How PRP Works in the Body
Platelets are best known for clotting, but they also carry tiny packets called alpha-granules filled with proteins that drive tissue repair. When PRP is injected into a damaged joint, tendon, or patch of skin, those platelets release growth factors that stimulate new blood vessel formation, recruit stem cells to the area, and trigger collagen production. The concentrated dose essentially amplifies the repair process your body would carry out on its own, just at a much lower intensity.
The concentration matters. In animal studies of tendon injuries, full pain relief required platelet counts around 1 million per microliter, while lower concentrations fell short. For promoting new blood vessel growth, roughly 1.5 million platelets per microliter appears to be the most effective threshold. This is why preparation technique is so important: a poorly made batch of PRP may not contain enough platelets to be therapeutically useful.
How PRP Is Prepared
The process starts with a standard blood draw, typically between 10 and 30 milliliters depending on the protocol. That blood goes into a centrifuge, which spins it at high speed to separate the components by weight. Red blood cells, the heaviest, sink to the bottom. Platelets and white blood cells settle into a thin middle layer. Plasma, the liquid portion, rises to the top.
Some clinics use a single spin, which is faster but produces a less concentrated product. A double-spin method adds a second round of centrifugation that packs the platelets more tightly, achieving roughly a fivefold concentration while maintaining platelet integrity. The entire preparation takes about 15 to 30 minutes and happens in the same appointment as the injection. An anticoagulant is added to the blood tubes beforehand to keep the sample from clotting during processing.
Common Uses in Orthopedics
The most established use of PRP is for joint and soft tissue injuries. It’s widely offered for knee osteoarthritis, tennis elbow, rotator cuff tears, Achilles tendon problems, and chronic low back pain. For knee osteoarthritis specifically, a 2021 meta-analysis of randomized controlled trials comparing PRP to saline injections found that both pain scores and functional measures favored PRP. According to Mayo Clinic researchers, the treatment shows a 60% to 70% chance of meaningful success, defined as at least a 50% improvement in pain and function lasting 6 to 12 months after injection.
Tendon injuries tend to respond well but require patience. Full recovery from a tendon-related PRP treatment can take three to six months, longer than for joint injections.
PRP for Hair Loss
PRP has become a popular option for androgenetic alopecia, the most common form of hair thinning in both men and women. The growth factors in PRP are thought to stimulate dormant hair follicles and extend the active growth phase of the hair cycle. Treatment protocols typically involve four to six sessions spaced two to four weeks apart, with results evaluated around four to nine months after the first session.
Most patients who respond to treatment notice thicker, denser hair in the treated areas, though individual results vary. Maintenance sessions every six to twelve months are generally recommended to sustain the effect.
Wound Healing and Diabetic Ulcers
PRP applied topically to chronic wounds, particularly diabetic foot ulcers, speeds up tissue closure. A systematic review found that wounds treated with PRP healed at nearly twice the rate of standard care: 0.68 square centimeters per week versus 0.39 square centimeters per week. This is one of the few uses where insurance coverage exists. Medicare covers PRP for chronic, nonhealing diabetic wounds for up to 20 weeks of treatment, provided FDA-approved equipment is used.
What Recovery Looks Like
The injection itself takes only a few minutes. You may feel pressure or mild discomfort at the injection site, and some soreness and bruising in the days that follow is normal. Most people return to desk work and light daily activities within a day or two, though the treated area needs to be protected from heavy strain.
For orthopedic uses, patients typically return to full normal activity around six weeks after the procedure, guided by their care team. It takes six to eight weeks to gauge whether your body is responding to the treatment, and full therapeutic effects can take three to six months to develop. This delay can feel frustrating, but it reflects the biology: PRP initiates a healing cascade, and tissue remodeling is a slow process.
Side Effects and Safety
Because PRP comes from your own blood, the risk of allergic reaction or rejection is essentially zero. The most common side effects are soreness and bruising at the injection site. Eating a meal and staying hydrated before the appointment helps prevent lightheadedness from the blood draw.
Less common risks include bleeding, tissue damage, infection, and nerve injury. These complications are rare with proper technique. The procedure is considered low-risk overall.
Who Should Avoid PRP
A 2025 international consensus outlined several situations where PRP should be delayed or avoided. Active bacterial infections need to be fully treated first. People with hepatitis C should complete antiviral treatment before receiving PRP. Those with HIV can receive treatment if their viral load is undetectable and their immune cell counts are adequate.
PRP should never be injected near any tumor, whether benign or malignant, or near areas of abnormal tissue growth. Low platelet counts from non-cancerous causes (above 50,000 per cubic millimeter) are not a barrier to treatment, but platelet abnormalities linked to blood cancers require specialist clearance. If you’re on dialysis, the injection needs to be scheduled on a non-dialysis day with close monitoring.
Cost and Insurance Coverage
A single PRP session typically costs between $500 and $2,500, and most conditions require multiple sessions. That adds up quickly: a three-injection series for a knee could run $1,500 to $7,500 out of pocket.
Outside of diabetic wound care, insurance coverage is extremely limited. Medicare does not cover PRP for osteoarthritis, tendon injuries, tennis elbow, rotator cuff tears, or chronic back pain, citing insufficient evidence. Most private insurers follow the same position. Cosmetic applications like hair restoration are never covered. This cost barrier is one of the biggest practical considerations for anyone weighing PRP against other treatments.