Kratom (Mitragyna speciosa) is a tree native to the tropical forests of Southeast Asia, traditionally used since antiquity for its stimulating, sedative and medicinal properties depending on the dose. Its main active alkaloid, mitragynine, acts on opioid and other receptors, and the plant has spread internationally in recent decades as a non-conventional substance, including in the management of opioid withdrawal. ICEERS gathers here ethnobotanical, pharmacological and harm reduction content related to kratom.