Osteoarthritis (OA) is the most common chronic joint disease, affecting 1.3 million Australians. It is a major cause of pain and disability, mostly affecting people aged 65 years or over. The main symptoms are pain, stiffness, and limitation of movement. Pain is initially felt in the joint during and after activity, but as the disease progresses it may occur with minimal movement or even during rest. It commonly affects the hips, knees, hands, and spine.
OA cannot be cured and there is wide variety of management options, varying from over the counter paracetamol to surgical joint replacement. A recent national health survey reported that 46% of people with OA are taking dietary supplements or natural remedies for the condition. Such widespread use of complementary medicines creates quite a challenge for both the patient and the general practitioner. Patients often don’t mention taking them as they are easily purchased over the counter at a pharmacy, health food store or supermarket. But what is the scientific evidence for their use? Are they safe? Do they have side effects? Do they interact with the conventional medications your doctor has advised you to take? Should your doctor be recommending you take them at all?
There are so many complementary medicines which are thought to benefit OA sufferers creating a state of confusion for all concerned. In this article, I have looked at some of the more common ones. Starting with Capsaicin, a herbal medicine extracted from chilli peppers. Capsaicin uses up Substance P, which plays an important role in the transmission of pain signals from nerve endings to the brain and is involved in activating inflammatory substances in joints. There are no major safety concerns in applying capsaicin gel/cream to a painful area of the body, although most people will feel a burning sensation when the gel comes into contact with their skin. There are no reported drug interactions or major safety problems and research shows that it can be effective in reducing pain and tenderness in affected joints.
Devil’s claw comes from a plant native to the deserts of South and South East Africa. It is not completely understood how it works but laboratory studies have found that extracts from the plant root can block several pathways which cause joint inflammation. Rare side effects include abnormal heart rhythms and internal bleeding. Less common side effects include rashes, gastrointestinal upset, headaches and loss of appetite. It also interacts with ibuprofen, digoxin and antacids. Research studies comparing the use of devil’s claw to a conventional anti-inflammatory medication demonstrated a slightly better improvement in pain symptoms and less side effects in patients taking devil’s claw.
Fish oils are rich in omega-3 essential fatty acids, which can regulate the body’s immune system and fight joint inflammation. Fish liver oil is also a rich source of vitamin A (A strong antioxidant) and vitamin D (Which is important for maintaining healthy joints). However, the largest trial comparing fish liver oil to regular anti-inflammatories showed no significant difference between the 2 treatment groups with regards to impact on pain and disability. In fact, both treatments failed to significantly reduce these symptoms.
Fish oil is considered to be well tolerated at therapeutic doses. However, certain environmental chemicals such as methylmercury and polychlorinated biphenyls (PCBs) can contaminate fish supplies and there’s a concern that taking very high doses of fish oil can cause a build-up of these chemicals in the body. Fish oil can interfere with blood clotting so shouldn’t be taken with anticoagulants.
Ginger is a plant native to Asia, West Africa and the Caribbean. Some laboratory and animal studies have found ginger extracts can reduce the production of several chemical substances that promote joint inflammation. Ginger also contains salicylates, which are transformed by the body into a chemical substance called salicylic acid. This inhibits the production of certain prostaglandins in the nerves, relieving pain and discomfort. Results from randomised control trials evaluating its role in patients with OA found that it has moderately beneficial effects in reducing pain and disability. It is relatively well-tolerated with minor side-effects, gastrointestinal disturbance and mouth irritation.
Glucosamine is an amino sugar made from shellfish. It is also found naturally in the body. It plays an important role in making glycosamino-glycans and glycoproteins, which are essential building blocks of many structures of the joints, including the ligaments, tendons, cartilage and synovial fluid. Side-effects, which are usually mild and infrequent, include stomach upsets, constipation, diarrhoea, headaches and rashes. Glucosamine shouldn’t be taken by people who are allergic to shellfish. The role of glucosamine in the treatment of osteoarthritis has been subject to more trials than any other complementary medicine and the results are mixed. Some trials have demonstrated the effectiveness of glucosamine sulphate when compared to placebo, but others have not. The size of effect is also, overall, modest. In conclusion, the evidence for use of glucosamine for management of OA is not convincing.
Rosehip oil comes from Rosa canina, a species of wild rose native to some regions in Europe, Africa and Asia. Rosehip is made from the fruits that usually develop after the bloom has died. Rosehip extract contains polyphenols and anthocyanins, which are believed to help relieve joint inflammation and prevent joint damage. It’s also rich in vitamin C, which has antioxidant properties. Side-effects are usually mild but include allergic reactions, constipation, diarrhoea and heartburn. The evidence available suggests that rosehip may be relatively well tolerated and may be effective in relieving some symptoms associated with OA.
Tumeric is a plant native to southern Asia. Studies on animals have shown that turmeric products have anti-inflammatory properties and human clinical trials haven’t found turmeric to be toxic when given at doses of 1–10 g a day. Turmeric increased the effects of anticoagulants or antiplatelet drugs in laboratory studies, but the effects on antiplatelet drugs haven’t been demonstrated in humans. The effectiveness of turmeric in osteoarthritis is uncertain due to the limited trial evidence.
Obviously, this is just a snapshot of some of the commonly available over the counter treatments for OA. Please advise your doctor if you are taking any so that they can work with you to determine the best course of treatment for your illness.
Author – Dr. Freyja Page
MB,BS (London), DCH
Dr Freyja Page is a GP Registrar with over 10 years hospital experience and 3 years consulting within the General Practice environment. She has diplomas in Obstetrics from The Royal College of Obstetricians & Gynaecologists and in Family Planning and Sexual health from Sexual Health and Family Planning Australia.
© Townsville & Suburban Medical Practice, 2018.