Cholestatic hepatitis from prolonged kratom use: a case report.

K ratom is an herbal product made from the leaves of Southeast Asian Mitragyna trees. The leaves can be chewed or an extract made and used as a powder or tablets. Kratom is used by local people to relieve fatigue and muscle aches and manage pain, diarrhea, or opioid withdrawal. The effects of kratom appear to be dose dependent, in that low doses tend to increase alertness whereas higher doses sedate. The active components of kratom are natural alkaloids, mitragynine, and 7-hydroxymitragynine (7-OHMG), which act on mu, delta, and kappa opioid receptors. 7-OHMG has been reported to have 13-fold higher potency than morphine. Kratom has been increasingly used in Western countries and the United States to counteract fatigue and anxiety and relieve opioid withdrawal symptoms. Literature reports of toxicity are rare, but are increasing in number. This case report describes intrahepatic cholestasis arising after intake of maeng da kratom, the Malay term used for extract derived from Mitragyna speciosa.