Prolotherapy is an alternative therapy that may help repair body tissues. It’s also known as regenerative injection therapy or proliferation therapy.

The concept of prolotherapy dates back thousands of years, according to experts in the field. There are different types of prolotherapy, but they all aim to stimulate the body to repair itself.

Dextrose or saline prolotherapy involve injecting a sugar or salt solution into a joint or other part of the body to treat a range of conditions, such as:

Many people say the injections help relieve pain, but scientists cannot explain how it works, and research has not confirmed that it is safe or effective.

Dextrose prolotherapy and saline prolotherapy involve injecting a solution containing irritants — a saline or dextrose solution — into a specific area where damage or injury has occurred.

It could help:

  • reduce pain and stiffness
  • improved strength, function, and mobility of the joint
  • increase the strength of ligaments and other tissues

Supporters say the irritants stimulate the body’s natural healing response, leading to the growth of new tissues.

People mostly use it to treat tendon injuries resulting from overuse and to tighten unstable joints. It may also relieve pain due to osteoarthritis, but research has not confirmed that this is the case, and there is not yet any evidence of long-term benefit.

The American College of Rheumatology and Arthritis Foundation (ACR/AF) do not recommend using this treatment for osteoarthritis of the knee or hip.

Platelet-rich plasma (PRP) injections are another type of prolotherapy that some people use for OA. Like saline and dextrose prolotherapy, PRP does not have the backing of research. Learn more here.

Prolotherapy may provide some pain relief.

In one study, 90 adults who had had painful OA of the knee for 3 months or more had either dextrose prolotherapy or saline injections plus exercise as a treatment.

The participants had an initial injection plus further injections after 1, 5, and 9 weeks. Some had further injections at weeks 13 and 17.

All those who had the injections reported improvements in pain, function, and stiffness levels after 52 weeks, but the improvements were greater among those who had the dextrose injections.

In another investigation, 24 people with OA of the knee received three dextrose prolotherapy injections at 4-week intervals. They saw significant improvements in pain and other symptoms.

A 2016 review concluded that dextrose prolotherapy could help people with OA of the knee and fingers.

However, the studies have been small, and researchers have not been able to identify how exactly prolotherapy works. One lab study concluded that it may work by triggering an immune response.

The AF suggests that its success may be due to a placebo effect, as injections and needling can often have a strong placebo effect.

Prolotherapy is likely to be safe, as long as the practitioner has training and experience in these types of injections. However, there are risks involved with injecting substances into a joint.

Possible adverse effects include:

  • pain and stiffness
  • bleeding
  • bruising and swelling
  • infection
  • allergic reactions

Depending on the type of prolotherapy, less common adverse effects are:

  • spinal headache
  • spinal cord or disk injury
  • nerve, ligament, or tendon damage
  • a collapsed lung, known as pneumothorax

There may be other risks that experts aren’t aware of yet, due to the lack of rigorous testing.

In the past, adverse reactions have occurred following injections with zinc sulfate and concentrated solutions, neither of which are commonly in use now.

Speak to your doctor before seeking this kind of treatment. They may not recommend it. If they do, ask them for advice on finding a suitable provider.

Before giving prolotherapy, your provider will need to see any diagnostic images, including MRI scans and X-rays.

Ask your doctor whether you should stop taking any existing medications before having the treatment.

During the procedure, the provider will:

  • clean your skin with alcohol
  • apply lidocaine cream to the injection site to reduce pain
  • inject the solution in the affected joint

The process should take around 30 minutes, including preparation, after you arrive at the facility.

Immediately after treatment, your doctor may apply ice or heat packs to the treated areas for 10–15 minutes. During this time, you will rest.

Then you’ll be able to go home.

Immediately after the procedure, you’ll likely notice some swelling and stiffness. Most people can resume normal activities by the next day, although bruising, discomfort, swelling, and stiffness may continue for up to a week.

Seek medical attention at once if you notice:

  • severe or worsening pain, swelling, or both
  • a fever

These could be a sign of infection.

Prolotherapy doesn’t have approval from the Food and Drug Administration (FDA), and most insurance policies won’t cover it.

Depending on your treatment plan, you may need to pay $150 or more for each injection.

The number of treatments will vary according to individual needs.

According to an article published in the Journal of Prolotherapy, the following are typical courses of treatment:

  • For an inflammatory condition involving a joint: three to six injections at intervals of 4 to 6 weeks.
  • For neural prolotherapy, for example, to treat nerve pain in the face: Weekly injections for 5 to 10 weeks.

Dextrose or saline prolotherapy involves injections of a saline or dextrose solution into a specific part of the body, such as a joint. In theory, the solution acts as an irritant, which may stimulate the growth of new tissues.

Many experts do not recommend this treatment, as there is not enough evidence to confirm that it works.

While it is likely to be safe, there is a risk of adverse effects, and you may experience discomfort for some days after the treatment.