Severe Drug-Induced Liver Injury Due to Self-administration of the Veterinary Anthelmintic Medication, Fenbendazole

Fenbendazole is an anthelmintic agent approved for veterinary applications. Even though it is not approved by the US Food and Drug Administration for human use, such use appears to be increasing due to the popularization of fenbendazole's potential anticancer effects by social media. We describe the first case of histologically confirmed severe drug-induced liver injury, hepatocellular pattern, associated with the self-administration of fenbendazole in a 67-year-old woman who presented with 2 weeks of jaundice. Liver function tests normalized in 3 months after the cessation of fenbendazole.