The science

Platelet-rich plasma (PRP) injections are gaining traction as a regenerative medicine treatment that can stimulate healing and help repair certain injuries. Platelets are the components of blood responsible for clotting and initiating tissue repair — and PRP delivers them at concentrations far higher than what circulates naturally, along with the growth factors they carry. The treatment is made from your own blood, and those concentrated platelets and growth factors are intended to help your body heal more effectively than it could on its own.

PRP is prepared by drawing your blood and spinning it in a machine called a centrifuge to separate and concentrate the platelets. The concentrated plasma is then injected into areas of injury or degeneration, most commonly in joints, tendons, and muscles.

PRP delivers a concentrated dose of growth factors and healing proteins directly to injured tissues. That’s because platelets contain tiny storage sacs, which release molecules that help reduce inflammation and promote tissue repair. These molecules stimulate cell growth, blood vessel formation, and the production of structural proteins that help rebuild damaged tissue. While these eventually resolve chronic pain, they initially trigger a brief, targeted inflammatory response to jumpstart the body’s natural repair process.

Ultimately, the effectiveness of PRP comes down to three things: a high-quality extraction, proper activation of the healing cells, and pinpoint accuracy during the injection.

What the research shows

Below are the conditions where PRP has been studied. Please also note our caveat emptor below, for important and added nuance.

Musculoskeletal conditions:

  • Arthritis of the knee: PRP offers functional improvement at 1-, 3-, 6-, and 12-month follow-up points and pain relief at 3- and 6-month follow-up points compared with placebo for the treatment of knee arthritis. Platelet concentration was found to influence treatment efficacy, with high-platelet PRP (>1 million per micro liter) providing better pain relief and more durable functional improvement than low-platelet PRP.
  • Rotator cuff problems: Steroids showed better outcomes in the short term but PRP showed better medium- and long-term changes in pain and function. People who received PRP were also less likely to need further injections or surgery within one year. However, the current data shows no clear benefit of PRP over placebo at any time point (again, see caveats below). 
  • Tennis elbow: Research shows that PRP provides little or no meaningful benefit compared to placebo injections for tennis elbow at 3, 6, and 12 months. 
  • Other musculoskeletal conditions: Evidence for PRP in hip arthritis and other musculoskeletal conditions is less clear, with some studies showing benefits, but overall limited evidence.

PRP beyond joints and tendons:

  • Chronic wound healing: PRP helps chronic wounds heal faster, including diabetic foot ulcers, venous leg ulcers, and pressure sores. Studies show PRP significantly improves wound closure rates compared to standard wound care alone. PRP shortens healing time and may reduce hospital stays without increasing complications.
    • It’s important to remember that PRP is an addition, not a replacement for standard care like offloading (taking pressure off a diabetic foot), compression therapy (for venous ulcers), or debridement (cleaning out dead tissue).
  • Hair loss: Research shows that PRP injections significantly increase the number of hair follicles, the thickness of hair, and density compared with placebo interventions. Patients also reported high overall satisfaction with the PRP treatment. Only temporary minor side effects were noted, including localized pain, bleeding, and itching.
  • Skin rejuvenation and esthetics: PRP is sometimes used for facial rejuvenation, often called a “vampire facial.” Studies suggest it may improve skin thickness and elasticity, while results for wrinkles, texture, and uneven skin tone are more mixed. Anecdotal satisfaction is generally high, and serious side effects have not been reported. PRP is also being studied for acne scars, vitiligo, and burn healing, but more research is needed.
  • Emerging uses: PRP is being studied for many other conditions, including gynecologic conditions (thin uterine lining, vaginal dryness, urinary incontinence), dental procedures, eye conditions (dry eye, corneal healing), and nerve injuries. These uses are still considered experimental, and evidence is limited.

Caveat emptor

Before discussing usage, it's important to ask a key question: when examining whether PRP is effective or not, what is the goal and are we comparing it to? 

As a general rule, corticosteroid injections provide robust, short-term pain relief, but can possibly impair the body’s natural healing process in the long run. So steroids generally beat PRP for short-term pain relief (usually quantified as less than two months), but by three to 12 months, PRP is usually more effective. However, the picture gets cloudy when you compare PRP to a placebo, and the treatment often does not beat the effectiveness of a placebo in the short-term or the long-term.

An additional note on study quality

There is significant variation in how PRP is prepared, the amount of platelets and white blood cells in each injection, and how it’s reported across different studies, making it difficult to compare results and determine the best approach. This may be why the data is quite mixed overall, with some studies showing a benefit over placebo and others showing no benefit.

Usage guidelines

PRP is made by drawing your blood (similar to a regular blood test) and spinning it in a centrifuge machine. The process takes about 15-30 minutes. Different preparation methods result in different concentrations of platelets and white blood cells. The optimal white blood cell content is still debated and may depend on the condition being treated.

Treatment schedule: Most treatment plans involve one to three sessions spaced 1-2 weeks apart. There is no standard dosing protocol, and treatment plans vary depending on your condition.

Safety: PRP is considered safe because it uses your own blood, so there is minimal risk of allergic reaction or disease transmission. However, careful administration in a proper clinical setting is important. The most commonly reported adverse reaction is infections following the injections. Common side effects include pain, swelling, or bruising at the application site, similar to other injections. Serious complications are rare.

Choosing a provider

No specific PRP system or device is considered the best. If you’re considering PRP, ask your health care professional about:

  • The platelet concentration in their PRP preparation. Research suggests that higher platelet doses (more than 1 million platelets per microliter) may be more effective
    • Specifically: You should ask if the provider measures and documents platelet counts for each treatment. Each preparation should be analyzed before injection, and patients should receive documentation of that analysis, which includes platelet count and other factors.
  • Their experience with PRP for your specific condition
  • The expected number of injections and cost (PRP is often not covered by insurance)
  • Ask about leukocyte content (leukocyte-poor vs. leukocyte-rich PRP), as this may affect outcomes for different conditions. For example, for tendons (like tennis elbow), some inflammation from white blood cells is actually helpful to jumpstart healing. For joints (like knee osteoarthritis), doctors usually prefer removing white blood cells to avoid unnecessary swelling.

The bottom line

PRP is a generally safe treatment option for certain musculoskeletal conditions, chronic wound healing, hair loss, and is emerging in a variety of other conditions. More standardized research is needed to determine the best preparation methods, patient selection, and treatment protocols. If you’re interested in trying it, find a health care professional you trust and who will answer your questions before diving in.