Q: A friend of my teenage daughter was telling her about a new, “natural” weight-loss medication that contains wild ginger. Besides the obvious (a teen should not be taking “drugs” to lose weight), I seem to remember a problem with wild ginger. Is this substance dangerous?
A source of the herbal drug aristolochic acid (AA), wild ginger is a plant in the birthwort family. Its common name may be explained by the fact that it smells and tastes somewhat like ginger. However, wild ginger is not related to the common herb, ginger, that is found in the grocery store.
After multiple incidents of acute kidney failure in Europe, China, India, and the Balkans were linked to AA, the FDA sent out warning letters in 2001.5 However, as the saying goes, what goes around, comes around. A new wave of “natural” weight-loss remedies containing AA has become available for sale to unsuspecting consumers over the Internet.
Wild ginger plants grow in temperate regions, with a kidney-shaped leaf—ironic, since ingesting this substance can induce kidney failure. In an article published in 2012, researchers reported that a Chinese company had replaced Stephania tetrandra with Aristolochia fangchi in their weight-loss formula, resulting in multiple incidents of kidney failure.6 In 2013, investigators from London and Germany showed that products containing AA were commonly available online.7
Symptoms of AA ingestion include acute kidney failure with normal blood pressure; a normochromic, normocytic anemia with a moderate amount of urine protein excretion (< 1.5 g/d); and urine sediment with a few red blood cells. The serum creatininehas been reported anywhere from 1.4 to 12.7 mg/dL on presentation,7 but due to AA-associated reductions in fluid and food intake (ie, its “weight-loss” component), this can quickly progress to kidney failure.
Discontinuing use of the herbal remedy does not appear to stop users’ progression to kidney failure, as damage to the interstitial cells is already done by the time of presentation.
AA use is also associated with an increased incidence of both kidney cancer and urinary cancer. Quite a high-risk “natural” herbal remedy!
Kim Zuber, PA-C, MSPS, DFAAPA,Department Co-editor
References
5. Boyle B. FDA warns consumers to discontinue use of botanical products that contain aristolochic acid (2001). www.hcvadvocate.org/news/NewsUpdates_pdf/2.1.1.2_News_Review_Archive_2001/aristocholic.pdf. Accessed April 5, 2013.
6. Asif M. A brief study of toxic effects of some medicinal herbs on kidney. Adv Biomed Res. 2012;1:44.
7. Gökmen MR, Cosyns JP, Arlt VM, et al. The epidemiology, diagnosis, and management of aristolochic acid nephropathy: a narrative review. Ann Intern Med. 2013;158:469-477.