Mitragyna speciosa (ketum, kratom or kratum, Thai: กระท่อม) is a tropical deciduous and evergreen tree in the coffee family (Rubiaceae) native to Southeast Asia in the Indochina and Malesia floristic regions. Its leaves are used for medicinal properties. It is psychoactive, and leaves are chewed to uplift mood and to treat health problems. M. speciosa is indigenous to Thailand and, despite growing naturally in the country, has been outlawed for 70 years and was originally banned because it was reducing the Thai government’s tax revenue from opium distribution.
Kratom behaves as a mu-opioid receptor agonist like morphine and is used in the management of chronic pain, as well as recreationally. Kratom use is not detected by typical drug screening tests, but its metabolites can be detected by more specialized testing. The pharmacological effects of kratom on humans, including its efficacy and safety, are not well-studied. Most side effects of kratom are thought to be mild, although isolated adverse effects such as psychosis, convulsions, hallucinations, sweating, nausea, vomiting, chest pain, dizziness and confusion have been reported, albeit rarely. There has been a reported case in which chronic use of M. speciosa was associated with bowel obstruction, as well as reports stating that the plant carries the potential for addiction and can lead to withdrawal symptoms.