In a medical first, a 38-year-old man with gallstones developed severe liver damage and jaundice after following the delusional advice of a practitioner of naturopathy, a pseudoscientific system that eschews evidence-based medicine.

Writing in BMJ Case Reports, doctors report that the naturopath told the man to take an excessive amount of Epsom salt for "stone dissolution." Such overdoses of the salt, aka magnesium sulfate, can cause diarrhea, breathing problems, kidney injury, and cardiac arrhythmias. But this is the first time doctors have ever reported that it caused liver damage.

Epsom salt is known to help with some conditions at lower doses. But, despite naturopathic claims of liver and gallbladder "flushes" and "cleanses," there is no evidence that Epsom salt can dissolve and help remove gallstones. In fact, even the actual medications that break up gallstones—such as ursodeoxycholic acid tablets—don’t work well and aren’t often prescribed. They can take years to dissolve the smallest of gallstones, which are typically little balls of cholesterol that clog up the bile-storing gallbladder. And once a patient stops taking the tablets, stones can form again. The recommended treatment for symptomatic gallstones is surgery to remove the gallbladder, which is a non-essential organ.

Epsom salt may have been a benign, if not simply useless, treatment if it hadn’t been given at such a potent dose. For example, when Epsom salt is used as an occasional saline laxative, doctors recommend that patients take just 10 to 30 grams in at least 250ml of water. The naturopath advised the man to take 45g every day for 15 days in an unspecified amount of water.

During the treatment, the man lost his appetite, his urine got darker, and he developed jaundice. Biopsies and scans revealed that his liver was enlarged and showed signs of tissue death and scarring. But tests for common liver diseases all came back negative.

After using a standard causality assessment tool, the doctors pinpointed the Epsom salt as the likely, but unexpected, cause of the man’s liver injury. The doctors told him to stop taking the salt and drink lots of water. After 38 days, tests showed that his liver function recovered.

The doctors noted that certain underlying conditions, such as nonalcoholic fatty liver disease, could increase the risk of developing liver damage while taking Epsom salt. But more research would be needed to establish that. What is clear, however, is that following the advice of a naturopath can be harmful to your health.

BMJ Case Reports, 2017. DOI: 10.1136/bcr-2017-221718 (About DOIs).