EPISTANE

Epistane is a designer anabolic steroid that appeared in dietary supplements sold online, often marketed as prohormones. In vitro studies using human hepatocytes demonstrate that even low concentrations (0.01 μM) upregulate bile acid synthesis genes and transporters, providing a molecular basis for the cholestasis observed clinically. Four documented cases of long-lasting cholestasis following epistane consumption showed 14- to 61-fold increases in serum bile acid pools, primarily conjugated cholic acid. Analytical studies confirmed that commercial epistane products contain not only the labeled compound but also desoxymethyltestosterone (madol) and isomeric impurities, raising additional safety concerns. No controlled human trials exist; all evidence comes from case reports, in vitro studies, and anti-doping analytical chemistry. The large phenotypic variability in bile acid synthesis enzymes may explain the idiosyncratic nature of epistane-induced liver injury.