Platelet Rich Plasma: How Does It Work, and Does It Work? What Is the Evidence?

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platelet rich plasma

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By Stuart M. Caplen, MD

In an effort to improve healing, injection of platelet rich plasma (PRP) is currently being utilized for many different medical conditions. In 2018 it was estimated that the global PRP market was expected to grow to between $380 million and $4.5 billion in the next ten years. The cost of a single treatment, which is not covered by most insurance, was estimated at approximately $500–$2,500, with patients often needing multiple treatments.[1] This article will discuss how PRP works and look at the current evidence as to whether it does improve healing for assorted conditions.

What Is Platelet Rich Plasma?

Platelet rich plasma is derived from blood drawn from an individual, which is then used in treating that same individual. The blood is specially processed to produce plasma, containing a large number of platelets. The theory behind PRP therapy is that an injection or deposition of concentrated platelets at sites of injury may aid tissue repair by releasing biologically active factors.[2]

Platelets contain seven growth factors required for wound healing. They also contain the proteins fibrin, fibronectin, and vitronectin that are used for cell adhesion in bone, connective tissue, and epithelial tissue. Platelet growth factors are stored in platelet alpha granules, and are released after an injury. These growth factors are secreted through the platelet cell membrane after the initiation of the blood clotting cascade. The growth factors next bind to the external surface of cells in the area where they were deposited or injected. The platelets continue to synthesize and secrete more growth factors for the approximately seven days of their life span.[3] PRP theoretically can stimulate the supraphysiological release of growth factors to jump-start healing in chronic injuries, and accelerate the acute injury repair process.[2] After the platelets die, macrophages take over wound healing regulation by secreting their own growth factors.

There are many different methods of preparing PRP. Variations in PRP include . . .

What are the variations in PRP?

How is PRP prepared?

What is Buffy Coat PRP?

What are the Uses of PRP?

Which specialities are using PRP?

Which dermatologic condition has not been associated with PRP treatment- acne scars, wrinkles and sagging, or hair loss?

For the answers, read the Conclusion of Platelet Rich Plasma


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Stuart M. Caplen, MD, FACEP, MSM

Dr. Caplen is a retired emergency medicine physician and former emergency department medical director, who also has a Master of Science in Management degree, and green belt certification in Lean/Six Sigma.


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