Arthritis Patients at Risk From Herbal Remedies Use

Patients with arthritis are more likely than the general population to be using herbal remedies, which increases the risk of serious interactions with prescribed medications, results of a British study suggest.

Although the use of complementary and alternative therapies by rheumatology outpatients is increasingly acknowledged, little attention has been given to the safety of these treatments.

Ginkgo biloba, devil’s claw, ginger and garlic may have anti- platelet or other anti-coagulant effects, and have been associated with haemorrhagic complications. These remedies may therefore exacerbate the gastrointestinal bleeding risk of non-steroidal anti- inflammatory drugs (NSAIDS) or corticosteroids. Echinacea poses a risk of hepatotoxicity when used with disease modifying antirheumatic drugs (DMARDS).

To examine the extent of the problem, researchers at Nuffield Orthopaedic Centre, Oxford, asked 238 rheumatology outpatients at three centres (Oxford, Swindon, Cirencester) to complete an anonymous questionnaire about their rheumatological diagnosis, conventional drug treatment, and use of herbal and over-the-counter remedies during the past six months.

Patients were asked whether they were aware of any side effects from the remedies, interactions with their prescription drug, and whether they had sought advice from a doctor or pharmacist before starting the remedy.

One-hundred-and-five (44%) patients had used herbal or over-the- counter remedies in the past six months. The most commonly used remedies were cod liver oil, glucosamine and/or chondroitin, and evening primrose oil.

Twenty-six (11%) patients were taking remedies that might interact with conventional drugs. Five of 120 (4%) patients receiving DMARDS were at increased risk of hepatotoxicity by also taking echinacea.

Twenty-four of 238 (10%) patients were at increased risk of bleeding disorders by also taking ginkgo biloba, garlic or devil’s claw with NSAIDS or corticosteroids. Twenty-four of 26 patients at risk of harmful interactions were unaware of this, and 10 of 26 had sought advice from a health professional before starting the remedy.

Doctors may not recognise potential adverse effects associated with herbal remedies, and patients may be reluctant to report either the use of herbal remedies or adverse effects, say the authors. Both patients and prescribers need more education on the risks and potential interactions of these preparations. (Holden W et al. Use of herbal remedies and potential drug interactions in rheumatology outpatients. Annals of the Rheumatic Diseases 2005; 64: 790).

Copyright TG Scott & Son Ltd. Jun 2005