Hyaluronic Acid

A 2022 review of the clinical trials showed that hyaluronic acid injections might slightly reduce knee pain from osteoarthritis. However, this small level of pain relief wasn't seen as very significant. The review also found that these injections could increase the risk of serious adverse effects.

Your doctor will inject the hyaluronic acid directly into the knee joint. Local anaesthetic is sometimes used before the injection.  Injections may be given once a week for three weeks or a single injection depending on the product/brand your doctor recommends.

Can other medicines be taken with hyaluronic acid?

Hyaluronic acid may be used with other arthritis medicines including:

• steroid medicines such as prednisolone or cortisone injections into the joint
• anti-inflammatory medicines (NSAIDs) such as naproxen (Naprosyn) or ibuprofen (Brufen, Nurofen)
• pain relieving medicines such as paracetamol.

There are separate information sheets for the medicines mentioned above.

Most side effects of hyaluronic acid are limited to the site of injection, some may be serious. Tell your doctor if you are concerned about possible side effects.

Most common possible side effects:

Local side affects may include:

• redness and tenderness at the site of the injection
• increased stiffness, swelling or warmth (inflammation) lasting 24 to 48 hours following the injection.

These local reactions may be treated by resting and applying ice to the injected area or by simple pain relievers.

Less common or rare possible side effects:

These include:

• Allergy including rashes, hives, itching, flushing and swelling of the face, tongue or throat, chest tightness and shortness of breath. If you experience any of these symptoms contact your doctor straight away.
• Less commonl,y a joint may become severely inflamed after injection. This may be due to acute arthritis from crystals in the joint. Very rarely an infection in the joint may develop after the injection. If the pain and swelling in the joint that was injected increases a great deal or the joint becomes red and hot, contact your doctor quickly.
• Other side effects may include headache, muscle pain, nausea, sore throat and flu-like symptoms.

After the injection

• Avoid strenuous activities (e.g. jogging or tennis) or long periods of standing for about 48 hours after the injection.

Infection

• Hyaluronic acid injections will not be given if you have an infection in your joint or a skin disease or infection around the area where the injection will be given.

Circulation

• Hyaluronic acid injections will not be given if you have circulatory problems in your legs.
• Tell your doctor if you have significant swelling or blood clots in your legs.

Allergy

• Hyaluronic acid injections will not be given if you have had a prior allergic reaction to hyaluronan-based products.
• Tell your doctor if you are allergic to products from birds such as feathers, eggs and poultry.

Use with other medicines

• You should tell all your doctors about all medicines you are taking or plan to take especially blood-thinning drugs such as warfarin.  This includes over the counter, herbal or naturopathic medicines.
• You should also mention your treatment when you see other health professionals.

Use in pregnancy and breastfeeding

• Hyaluronic acid has not been tested in pregnant women or women who are breastfeeding.
• It is important to tell your doctor if you are, or intend to become pregnant or if you are breastfeeding.

• You should tell your doctor if pain and swelling in the joint increases following the injection.
• You should tell your doctor if your joint becomes red and hot following the injection.