What is PRP therapy, in plain terms?

Written by Oscar Tellez, founder of Regen Med Academy. Oscar is not a clinician. This post is education for licensed providers and is not medical advice. Last updated October 13, 2026.

PRP stands for platelet-rich plasma, and PRP therapy is the use of a patient’s own plasma after the platelets in it have been concentrated. A provider draws a small sample of blood, spins it, and injects the platelet-rich part back into the same patient. The devices that prepare PRP are FDA cleared for use with bone graft material, so injecting it is an off-label use. One major medical group now recommends against it for knee and hip osteoarthritis, and this post covers that too.

What does PRP stand for?

The three letters stand for platelet-rich plasma, and each of the three words tells you something. Let’s take them one at a time.

Plasma is the liquid part of blood. Platelets are tiny cell fragments that float in that liquid, and they are best known for the part they play in clotting. Rich only means that each drop of the sample holds more platelets than a drop of the patient’s blood did.

So PRP is plasma that holds more platelets, drop for drop, than plain blood does. That is platelet-rich plasma explained in one sentence, and it is short enough for a new staff member to learn on day one.

FDA says it in one line. One of its guidance documents describes PRP as “blood taken from an individual and given back to the same individual as platelet rich plasma.”

You will also hear the word autologous. Autologous means the material comes from the patient’s own body and goes back into that same patient. The PRP that a clinic makes is autologous, which is why no donor is part of it.

How is PRP made?

PRP is made in three steps, and you can remember them as draw, spin and separate.

The first step is the draw. A trained staff member takes a small sample of blood from a vein, much the same way blood is drawn for a lab test. FDA’s device listing calls it “a small sample of peripheral blood,” and peripheral just means blood from an ordinary vein, like the one in the arm.

The second step is the spin. The sample goes into a centrifuge, which is a machine that spins it at high speed. The spinning sorts the blood by weight, so the red cells sink to the bottom and the plasma stays on top.

The third step is to separate. The platelet-rich part is drawn off, and the rest is left behind. In FDA’s words, the system “uses centrifugal and/or filtration methods to separate the whole blood into components, after which the platelet rich plasma is withdrawn.”

Some systems spin the blood once and some spin it twice. We have a full post on single spin and double spin preparation if you want that detail. The speeds, the times and the volumes belong to the system you own, and they are written in its instructions for use.

What is in PRP, and why do preparations differ?

Every PRP sample has plasma and platelets in it. What else is in the syringe depends on the system and on the patient.

A sample can also hold white blood cells, which are called leukocytes, and it can hold some red cells. One system leaves most of the white cells out, and another keeps a lot of them in. That is where the terms leukocyte-poor and leukocyte-rich come from.

Doctors ask me all the time, is it leukocyte-rich or leukocyte-poor PRP? Well, first of all, which leukocytes are you talking about? White blood cells come in several kinds, and a label that says rich or poor does not tell you which kinds are in the syringe.

The platelets differ too. Two systems can start with the same blood and end with a different number of platelets in a different amount of plasma. No two patients start with the same blood, so the starting point moves as well.

Why does this matter to a provider? It matters because the PRP in a published paper may not be the PRP in your tube. An overview from the American Academy of Orthopaedic Surgeons, which read the knee research through August 2021, listed “inconsistent reporting of leukocyte and platelet concentrations” among the limits of that research. In plain words, the papers did not all report what was injected in the same way.

Platelets also carry proteins that are called growth factors, and you will hear that term in a lot of sales pitches. We have a post on growth factors in regenerative medicine that covers the biology. I am not going to tell you here what they do for a patient, because that would be a claim.

What is PRP and how does it work?

That question has two halves, and the two halves do not get the same kind of answer.

How does the procedure work? You just read that half. The blood is drawn, spun and separated, and then the provider injects the platelet-rich part into the same patient.

How does PRP work inside the body? That half is a research question, and it is not settled. Researchers are still looking at what a concentrated dose of a patient’s own platelets does in a joint, a tendon, the skin or the scalp. FDA has cleared the devices for one stated use, and it has not approved PRP as a treatment for any condition.

Here’s the problem with the phrase “how it works.” The phrase takes for granted that it does, and a clinic cannot take that for granted in an ad or on a web page. The FTC holds a marketer responsible for claims that are “suggested or reasonably implied,” and not only for the ones that are spelled out.

So what do you say when a patient asks? You say what PRP is, you say that its use by injection is off-label, and you go over what the research says and where it stops. That answer takes longer than a slogan does, and it belongs in a visit and not in an ad.

Where do clinics use PRP?

Clinics use PRP in four main areas, and our own courses are built around the same four. Every one of them is an off-label use.

• Joints and soft tissue: orthopedic, sports and pain practices inject PRP into joints, tendons and ligaments, and that is an off-label use.
• Skin: aesthetic practices use PRP in the skin of the face and other areas, and that is an off-label use.
• Hair: some practices inject PRP into the scalp, and that is an off-label use.
• Sexual health: some practices use PRP in women’s and men’s sexual health, and that is an off-label use.

What does off-label mean? It means a cleared device is being used for a purpose that its clearance does not name.

Is off-label use allowed? Federal law leaves that call to the provider. It says nothing in the device law limits a practitioner’s authority “to prescribe or administer any legally marketed device to a patient for any condition or disease within a legitimate health care practitioner-patient relationship.”

That sentence covers what a provider may do with a patient. What a clinic may say about that use in its marketing is a separate question, and the same law keeps the limits on promoting unapproved uses.

A place on this list also does not mean the evidence supports that use. The list only tells you where PRP shows up in practice today.

What is the FDA status of PRP?

Here is the FDA status in three sentences. The devices that prepare PRP are FDA cleared for use with bone graft material. Injecting PRP into joints, tendons, ligaments, skin or scalp is an off-label use. Cleared is also not the same as approved, so nobody should call PRP or a PRP kit “FDA approved.”

FDA lists these systems under the name “platelet and plasma separator for bone graft handling.” Its definition of the device is the “preparation of autologous platelet rich plasma from a small sample of peripheral blood for mixing with bone graft to improve handling characteristics.” Look at the purpose that definition names. It is mixing with bone graft, and it does not name an injection into a knee, a face or a scalp.

What does cleared mean? FDA says a 510(k) is a submission made “to demonstrate that the device to be marketed is as safe and effective, that is, substantially equivalent, to a legally marketed device.” In plain words, the maker showed that its device is much like one that was already on the market. That is a finding about a device, and it is not a finding about PRP as a treatment for any condition.

As of October 5, 2026, no PRP product appears on FDA’s list of approved cellular and gene therapy products. Each cleared system also has its own clearance, and the words can differ from one system to the next. So read the 510(k) for the exact system you own.

What does the evidence show, and what does it not show?

This part is easy to skip, so let’s slow down here.

Start with joints, because that is where the plainest statement is. In its 2026 update, the American College of Rheumatology wrote, “In people with knee and hip OA, we strongly recommend against PRP treatment.” OA is short for osteoarthritis. The group’s board approved that summary on September 8, 2026, and the summary says the full paper is still to be submitted for publication.

What do trials of PRP in the knee measure? One example is a randomized trial published in JAMA in 2021. It followed 288 patients with mild to moderate knee OA, who got three weekly injections of either leukocyte-poor PRP or saline.

That JAMA paper measured the change in knee pain scores and in cartilage volume over 12 months. The authors wrote that PRP, compared with saline, “did not result in a significant difference in symptoms or joint structure at 12 months.” They also wrote, “These findings do not support use of PRP for the management of knee OA.”

One more document looked across more of the knee research, and it is older than the ACR update. The American Academy of Orthopaedic Surgeons put out an overview of the knee research through August 2021. The document says it “does not make recommendations for or against the use of platelet rich plasma.”

That overview is not an official AAOS position. It describes the papers it read as having “heterogenous and sometime contradictory findings,” which means they did not all point the same way. It also says that “whether PRP can improve the structure or functioning of the osteoarthritic joint remains unclear.”

So where does the evidence stop? For knee and hip osteoarthritis, a major medical group now recommends against PRP. For tendons, ligaments and other joints, this post does not cite a guideline, and you should read the research on the exact condition you plan to see. For skin, hair and sexual health, this post does not sum up the research at all, because a short summary turns into a claim very fast.

FDA also has a page for patients, current as of April 8, 2024, that says, “Regenerative medicine therapies have not been approved for the treatment of any orthopedic condition.” Its examples include osteoarthritis, tendonitis, knee pain and shoulder pain. That page speaks about the whole field and does not name PRP, but a provider who offers PRP for those conditions should have read it.

Who performs PRP?

A licensed provider performs PRP, and that provider’s own state license decides what the person may do.

Who can attend a course is a question providers ask us. Our answer is anyone legally able to provide the treatment, and that includes physicians, nurse practitioners, PAs, nurses and others. What you may perform is set by your own state license and board. A Certificate of Completion does not extend it.

A PRP visit also holds three separate tasks, which are the draw, the spin and the injection. Your state may let one staff member do the first two and require a different license for the third. So the real question is who may do each part, and your board answers it.

For nurse practitioners, the answer can change a lot from state to state. The AANP sorts the states into full practice, reduced practice and restricted practice, and its page is a good first stop.

State law in this field changes, sometimes more than once a year. Our reading of each state, with its sources and the date we checked, is on the rules by state page. It is a starting point, not legal advice. The authority on your own scope is your licensing board, not us.

How can my front desk explain PRP on the phone?

Your front desk needs one short, true definition and nothing else. Here is a version they can keep on a card by the phone.

“PRP stands for platelet-rich plasma. It is made from a small sample of your own blood, which we spin to concentrate the platelets. The provider can go over it with you at a visit and tell you whether it is an option for you.”

Look at what the card leaves out. It does not say what PRP does, it does not name a condition, and it does not promise anything.

What if the caller asks, does it work? The front desk does not answer that question. They can say that the provider goes over the research at the visit, and then they can offer a time to come in.

What if the caller asks about FDA? There is a plain, true answer to that one as well, as long as it fits your system. The system that prepares PRP is FDA cleared for use with bone graft material, and using PRP by injection is an off-label use.

A phone call is short, so the phone is the wrong place for a clinical answer.

Where does training fit in?

A shared definition is the first step, and it is also the easy one. Doing the draw, the spin and the injection with your own hands is a different kind of learning.

I have spent ten years in this field, and I started in 2016 by selling PRP kits to orthopedic, aesthetic and other practices. Here is the order I give providers: “Define the terms, ask the questions, and do it right.” This post is a PRP treatment overview, so it is only the first of those three.

It is the soil before the seed. The basics come before any injection, and a plain definition that your whole team shares is one of the basics.

When you are ready for the hands-on part, our Introduction to PRP for Musculoskeletal Injuries course is private training, built around your own cases. The theory comes to you online, and the hands-on day is in person. It is hands-on with a consenting patient, under supervision, and every licensed person in the room performs within their own scope.

We also teach PRP for aesthetics and hair loss and for sexual health, and the PRP training page shows how each one is set up.

There are limits, and we say them out loud. A day or a weekend does not make a specialist, and one course is a place to begin. We also do not offer CME, credit hours or accreditation of any kind.

If you are still choosing a program, our post on which PRP training program is right for your practice lists the questions to ask any course, including ours.

Frequently asked questions

Is PRP the same as stem cell therapy?

No. PRP is platelets in plasma, made from the patient’s own blood, and nobody should call a tube of spun blood a stem cell product. The two terms get mixed up in marketing, so ask what is in the syringe before you put any label on it.

Does PRP come from a donor?

No. The PRP made in a clinic comes from the patient and goes back into the same patient. FDA’s device definition uses the word autologous, which means the material comes from the patient’s own body. A product that comes from a donor is a different kind of product, and it stands on different regulatory ground.

Can my website say that PRP is FDA approved?

No. The devices that prepare PRP are cleared, and cleared is not approved. FDA also says, “Mere registration of an establishment or listing of a drug or device does not denote approval of the establishment, the drug or device.” If you mention clearance at all, say what the system is cleared for, and say that injecting PRP is an off-label use.

Is PRP covered by insurance?

That is a question for your biller and for each payer, and we do not answer it. Coverage can differ by plan, by payer and by use, so do not guess, and do not let your front desk guess. Get the answer from the payer in writing before you quote anything to a patient.

Do I need a special certification to offer PRP?

There is no government-issued PRP certification that gives you the right to inject. The right comes from your state license and your board. A course can give you a certificate that documents your training. Ours is called a Certificate of Completion, and it is not a license, a board certification or a credential.

How long does it take to make PRP?

It depends on the system. Each system has its own steps, speeds and spin times, and they are written in its instructions for use. Ask the vendor to run one full cycle in front of you, from the draw to the filled syringe, and time it yourself. Then build your schedule around what you saw.

Key takeaways

• PRP stands for platelet-rich plasma, which is platelets concentrated from the patient’s own blood.
• What is in the syringe differs by system and by patient, so always ask which PRP a paper used.
• The devices that prepare PRP are FDA cleared for use with bone graft material, and injecting PRP is an off-label use.
• The American College of Rheumatology’s 2026 update strongly recommends against PRP for knee and hip osteoarthritis.
• Your state license and board set who may draw, spin and inject, and a certificate does not change that.
• Your front desk should define PRP and stop there, with no claims and no promises.

RMA disclosure

Regenerative Medicine Academy (RMA) is an education company. We train licensed providers in some of the techniques this post covers. This post is education only. It is not medical, legal, business, tax or financial advice.

It is your responsibility to confirm the modality is legal in your state for your license. Do that before you book.

Your next step

Give your team the plain definition and the phone card, and read the sources linked above before the next patient asks about PRP. When you want to move from the definition to the hands-on work, see how our intro PRP course is set up. You can request a date now, and a person will read it and call you back within one business day. If you would like to start with the rules, get the free FDA course.