A commonly used herbal remedy that is banned in the U.S. and many European countries may still be harming users in Asia.
Since researchers connected an epidemic of kidney disease among Belgium women in the early 1990s to herbal medicines from a weight loss clinic, scientists have monitored the remedy for other potential health risks.
During the initial outbreak, scientists traced the kidney problems to aristolochic acid (AA), which belongs to a group of plants known as birthwort or Dutchman’s pipe. The agent is used for weight loss and to treat asthma and arthritis. But since the epidemic, herbs with aristolochic acid have been banned for medicinal uses in many countries, including the U.S. Researchers at King’s College London, however, now report in the Annals of Internal Medicine that millions of people are still being exposed, especially in Asia.
The scientists, led by Graham Lord, the director of the National Institute for Health Research Biomedical Research Centre at Guy’s and St Thomas’ NHS Foundation Trust and King’s College London, found that herbal medicines containing the acid are still found in China and other Asian countries and can be purchased online. “The reason we wrote this paper is to provide a diagnostic classification for aristolochic acid nephropathy (AAN) [the type of kidney failure associated with the agent]. For countries that haven’t asked the question of whether this is present, here is diagnostic criteria. We just don’t know what the levels of exposure are throughout the world,” he says.