Kratom

Mitragyna speciosa is a tropical evergreen tree of the Rubiaceae family native to Southeast Asia. It is indigenous to Cambodia, Thailand, Indonesia, Malaysia, Myanmar, and Papua New Guinea, where its dark green, glossy leaves, known as kratom, have been used in herbal medicine since at least the 19th century. They have also historically been consumed via chewing, smoking, and as a tea. Kratom contains multiple alkaloids that bind to opioid receptors, most notably as partial μ-opioid agonists. Kratom can also be subjectively stimulating to some, though this is likely not achieved through typical stimulant mechanisms, nor is this a universal effect.

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