Guggulsterone is a phytosteroid found in the resin of the guggul plant, Commiphora mukul. Guggulsterone can exist as either of two stereoisomers, E-guggulsterone and Z-guggulsterone. In humans, it acts as an antagonist of the farnesoid X receptor, which was once believed to result in decreased cholesterol synthesis in the liver. Several studies have been published that indicate no overall reduction in total cholesterol occurs using various dosages of guggulsterone, and levels of low-density lipoprotein increased in many people. Nevertheless, guggulsterone is an ingredient in many nutritional supplements. Guggulsterone was also found to have interactions with the viral ADP ribose phosphatase enzyme of SARS-CoV-2 and has been proposed as a potential candidate for the development of therapeutics for the treatment of COVID-19.