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Updated June 05, 2014.

Thunder God Vine (Triptergium wilfordii Hook F) is a Chinese herbal remedy which has been used for many years to treat joint pain, inflammation, and overactivity of the immune system. Thunder God Vine is a perennial vine found in China, Japan, and Korea. The extract that is used in traditional Chinese medicine is obtained by skinning the root of the Thunder God Vine. The root extract, according to the National Institutes of Health, is not currently manufactured or sold in the U.S however.

While the product can sometimes be obtained from outside the U.S., the safety and effectiveness cannot be assured.

Study Results

According to the National Center for Complementary and Alternative Medicine (NCCAM), while earlier studies have suggested that Thunder God Vine may decrease inflammation, suppress the immune system, as well as have anti-cancer properties, few of the studies could be classified as high quality. The first study in the U.S. to test Thunder God Vine on rheumatoid arthritis involved only 21 patients in 2002. One large study, funded by the National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) and published in the Annals of Internal Medicine in 2009, compared the extract of Thunder God Vine to sulfasalazine, a disease-modifying anti-rheumatic drug (DMARD) used to treat rheumatoid arthritis. There were 121 patients in the 24-week study. Results showed that there was more improvement in symptoms with Thunder God Vine than sulfasalazine.

Preliminary study results, published April 14, 2014, in the Annals of the Rheumatic Diseases, suggest that Thunder God Vine appears to have clinical benefit and may improve rheumatoid arthritis symptoms as well as methotrexate.

The study, involving 207 patients with active rheumatoid arthritis, compared Thunder God Vine to methotrexate over 24 weeks. More than half of the study participants who were taking Thunder God Vine alone achieved ACR50. Comparatively, 46% of participants taking methotrexate achieved ACR50. Participants taking both Thunder God Vine and methotrexate showed the most improvement with about 77% achieving ACR50. One significant limitation of the study was that it was not a blinded study, meaning, doctors and patients knew who was receiving Thunder God Vine and who was receiving methotrexate. For the study to have more merit, a blinded trial would be needed to eliminate the possibility of placebo effect. It is also important to remember that this trial only assessed improvement in signs and symptoms. Methotrexate is used to reduce signs and symptoms of rheumatoid arthritis, as well as slow disease progression. 

Potential Side Effects

There can be serious side effects if Thunder God Vine is not extracted from the skinned root cautiously. The leaves, flowers, and skin of the root are highly poisonous and can even cause death. Aside from these serious side effects, Thunder God Vine has been associated with gastrointestinal side effects, upper respiratory infections, hair loss, headache, menstrual changes, and skin rash. In women who take Thunder God Vine for more than 5 years, there may be decreased bone mineral density. Chemicals in Thunder God Vine may alter sperm and decrease fertility in men.

The Bottom Line

There need to be more high quality studies to evaluate and confirm the safety and effectiveness of Thunder God Vine for rheumatoid arthritis.

<sub>Sources:

Comparison of Tripterygium wilfordii Hook F with methotrexate in the treatment of active rheumatoid arthritis (TRIFRA): a randomised, controlled clinical trial. Annals of the Rheumatic Diseases. Qian-wen Lv, et al. Published online April 14, 2014.
http://ard.bmj.com/content/early/2014/03/18/annrheumdis-2013-204807

Chinese Thunder God Vine Gives Relief from Rheumatoid Arthritis Symptoms. NIAMS. October 2002.
http://www.niams.nih.gov/News_and_Events/Spotlight_on_Research/2002/thunder.asp

Comparison of Tripterygium wilfordii Hook F Versus Sulfasalazine in the Treatment of Rheumatoid Arthritis: A Randomized Trial. Annals of Internal Medicine. August 18, 2009.
http://annals.org/article.aspx?articleid=744661</sub>