by Elizabeth Freedman

The roots of Thunder God Vine, a plant whose leaves and flowers are highly toxic, have been used medicinally in China for over 400 years. A root extract of this plant was shown to safely and effectively reduce pain and inflammation in a small group of people with treatment-resistant rheumatoid arthritis, according to a study funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS). The randomized, double-blind, placebo-controlled trial, published in the July issue of Arthritis & Rheumatism, is the first to test the use of an extract of this vine in rheumatoid arthritis patients in the United States.

Twenty-one rheumatoid arthritis patients completed a 20-week clinical trial of the ethanol/ethyl acetate extract. Patients were randomly assigned to one of three treatment groups: placebo, low-dose extract, or high-dose extract. After four weeks, 80 percent of patients in the high-dose group and 40 percent in the low-dose group showed rapid improvement in symptoms compared with no improvement in the placebo group. Side effects were minor for all three treatment groups. Longer term studies with larger numbers of patients are needed to confirm the safety and benefits of the treatment. According to senior author Peter Lipsky, M.D., scientific director of NIAMS, the extract is a particularly promising treatment for rheumatoid arthritis. It is unique, because it slows down the overactive immune system, reduces inflammation by turning off inflammatory genes such as tumor necrosis factor alpha, and reduces the activity of B and T cells. Dr. Lipsky believes this plant extract has the potential to treat other immune diseases such as lupus, and is planning further studies. The extraction process, although time-consuming, is critical because it transforms the otherwise toxic and deadly Thunder God Vine into a therapeutic treatment.

Rheumatoid arthritis, a chronic inflammatory disease of the joint lining, often results in pain, stiffness, swelling, and loss of joint function. It occurs two to three times more often in women than in men.


Tao X, Younger J, Fan F, Wang B, Lipsky P. Benefit of an extract of Tripterygium Wilfordii Hook F in patients with rheumatoid arthritis. Arthritis & Rheumatism 2002;46(7):1735-43.

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