The evidence for prolotherapy is WEAK and mixed.
It means injecting an irritant, usually a sugar (dextrose) solution, into a sore tendon, ligament or joint. The idea is that the irritation sets off a healing response.
Some small studies look positive, especially for knee arthritis and heel pain. But when dextrose injected into the knee joint is compared with salt water, it probably makes little or no difference. For long-term low back pain, the injections on their own didn’t work in trials.
US rheumatologists, in their latest guidance, advise against it for knee and hip arthritis. It’s generally safe, but it usually takes several sessions, and it’s rarely covered by insurance.
What prolotherapy is
- The injection: a small amount of an irritating solution, most often dextrose, injected where a tendon or ligament attaches to bone, or into a joint
- The idea: a short burst of irritation is meant to trigger the body’s repair process and strengthen the tissue. This hasn’t been proven
- Where it’s used: knees, shoulders, heels, the Achilles tendon and the lower back, among others
- A course: usually 3 to 6 injections over several sessions
- Not the same as PRP: PRP uses a concentrate of your own blood, and stem cell injections use cells from bone marrow, fat or donated tissue
What the research shows
Most prolotherapy studies are small, and many have design flaws. That makes the results hard to trust in either direction.
- Knee arthritis: injected into the joint, it probably makes little or no difference compared with salt water. Injections in and around the knee may help more in the long run than physio alone, but that evidence is low quality. See knee arthritis
- Heel pain (plantar fasciitis): small studies suggest it may help more than salt water, and about as much as shockwave therapy. The evidence is low quality. See plantar fasciitis
- Shoulder tendon pain: results are very uncertain. See rotator cuff tendinopathy
- Achilles and other tendons: too little good research to say. Loading exercise has far better support. See Achilles tendinitis
- Long-term low back pain: on its own, it did no better than dummy injections. Combined with exercise and manual therapy, some people improved, but it’s unclear which part helped
Weak evidence isn’t proof that it fails. It’s a reason not to pay for a long course on hope.
Is prolotherapy safe?
- Soreness afterward is expected: more pain and stiffness at the injection site for a few days is common. It’s meant to irritate
- Bruising: possible but uncommon
- Infection: rare, as with any injection
- The safety picture is incomplete: many studies didn’t check carefully for side effects, so rarer problems may be missed
The Cleveland Clinic overview of prolotherapy sums it up: it isn’t a standard treatment for any condition, and the research is inconclusive.
Cost and insurance
- Usually self-paid: most insurance plans don’t cover it. In the US, Medicare doesn’t pay for it at all
- It adds up: it can cost hundreds of dollars per session, and a course takes several sessions
- Get the total in writing before you start, and be wary of paying for a large package upfront
Warning signs in a clinic
- Promises to “regrow” cartilage or ligaments: this hasn’t been shown
- Claims it can replace surgery for almost anyone
- No exercise plan alongside it: for tendons and arthritis, exercise is the treatment with the best evidence
- Endless sessions: no agreed point at which you’ll stop if it isn’t helping
What has stronger evidence
- For tendons: a progressive loading program, done for at least 12 weeks. Tendons respond to load, not rest
- For knee and hip arthritis: strengthening, staying active and weight loss if needed. A steroid shot can calm a bad flare
- For long-term back pain: regular exercise you can keep doing, and staying active
Questions to ask before you pay
- What exactly will you inject, and where?
- How many sessions, and what’s the total cost?
- How will we know if it’s working, and when will we stop if it isn’t?
- What exercise should I do alongside it?
- Will you use ultrasound to guide the needle?
Call your doctor today if
- The area gets hotter, redder and more swollen after two or three days instead of settling
- You have a fever or chills, or feel unwell
- A joint becomes very painful and swollen and you can’t use it
Get it checked if
- Soreness after an injection lasts more than about a week
- You’ve had a full course and noticed no change
- You’re being offered more sessions without a clear reason
- A tendon suddenly gives way or you feel a snap
Prolotherapy might help a stubborn tendon or joint, but loading it is what reliably does.