Fulminant liver failure due to usnic acid for weight loss

Am J Gastroenterol. 2004 May;99(5):950-2. doi: 10.1111/j.1572-0241.2004.04165.x.


The use of complementary and alternative medicine (CAM) in developed countries has increased significantly over the years. Among the most popular are the weight loss supplements or "fat burners." Liver failure due to these popular remedies has been widely recognized. Usnic acid has been an ingredient of dietary supplements that cause liver failure. Its hepatotoxicity has not been recognized because it is usually mixed with other ingredients that are presumably hepatotoxic. We describe a case of a 28-yr-old woman who presented with fulminant liver failure requiring orthotopic liver transplantation, after taking pure usnic acid for weight loss. This is the first report on fulminant liver failure associated with the ingestion of pure usnic acid. A discussion about hepatotoxicity of the different compounds of dietary supplements is presented. This is a reminder for the clinicians about the potential side effects of CAM.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Benzofurans / administration & dosage
  • Benzofurans / adverse effects*
  • Dietary Supplements / adverse effects*
  • Female
  • Follow-Up Studies
  • Humans
  • Liver Failure / chemically induced*
  • Liver Failure / physiopathology
  • Liver Failure / surgery*
  • Liver Transplantation
  • Obesity / drug therapy
  • Risk Assessment
  • Weight Loss / drug effects


  • Benzofurans
  • usnic acid