NEW YORK (Reuters Health) - A small study suggests that an herb used for many years in traditional Chinese medicine may help ease the symptoms of rheumatoid arthritis, US researchers report.
The herb is called Tripterygium wilfordii Hook F (TWHF), known also by the Chinese translation for "thunder god vine." Chinese medicine practitioners use extracts from the vine to treat arthritis and other disorders of the immune system.
Dr. Xuelian Tao of the National Institutes of Health ( news - web sites) and colleagues report that patients who took capsules of different doses of TWHF were more likely to experience a reduction in their symptoms of rheumatoid arthritis than those given pills containing inactive ingredients.
Rheumatoid arthritis is a chronic disease in which the body's own immune system attacks the tissue lining the joints. It is more common in women, tends to strike between the ages of 36 and 50, and results in chronic destruction and deformity of the joints.
Many patients with rheumatoid arthritis try to alleviate the joint pain and stiffness associated with their condition with medications such as non-steroidal antiinflammatory drugs (NSAIDs) or steroid drugs called glucocorticoids. However, these drugs carry risks of side effects, including osteoporosis and gastrointestinal problems such as ulcers or bleeding.
In the current study, published in the July issue of Arthritis & Rheumatism, Tao and colleagues compared the effects of an extract of TWHF to an inactive drug, or placebo, in 35 patients with rheumatoid arthritis. Patients were given placebo, a low dose of TWHF (180 milligrams) or a high dose of the extract (360 milligrams) each day for 20 weeks.
Fourteen of the original patients withdrew from the study before the end of the 20 weeks, citing various reasons, the authors note. One patient dropped out of each of the three treatment groups due to side effects.
Of the patients who completed the trial, 8 who were given the high dose of the treatment, and 4 given the low dose, experienced at least a 20% improvement in their symptoms. None of the patients given a placebo drug experienced a similar improvement, Tao and colleagues note.
Six patients taking the low dose of TWHF and 5 of those taking the high dose reported side effects as a result of the treatment, the authors add, which included hair loss, heartburn, and, most commonly, diarrhea. However, Tao and colleagues write, another 4 patients taking placebo also reported side effects similar to some of those noted in the treatment group, suggesting that TWHF may not be the cause of many of the concurrent ailments.
"Many of the side effects were noted in patients treated with placebo as well as in those treated with the extract, suggesting that the side effects may not be specifically associated with administration of the drug," the authors write.
Based on the findings, Tao and colleagues suggest that TWHF may alleviate the symptoms of rheumatoid arthritis by both suppressing immune system activity and reducing inflammation.
SOURCE: Arthritis & Rheumatism 2002;46:1735-1743.