Mitragyna speciosa is an evergreen tree that can grow to a height of 25 m (82 ft) tall and the trunk may grow to a 0.9 m (3 ft) diameter. The trunk is generally straight and the outer bark is smooth and grey. The leaves are dark green and glossy, and can grow to over 14–20 cm (5.5–7.9 in) long and 7–12 cm (2.8–4.7 in) wide when fully open, are ovate-acuminate in shape, and opposite in growth pattern, with 12–17 pairs of veins. The flowers grow in clusters of three at the ends of the branches. The calyx-tube is 2 mm (0.079 in) long and has 5 lobes; the corolla-tube is 2.5–3 millimetres (0.098–0.118 in) long. M. speciosa is indigenous to Indonesia, Thailand,Malaysia, Myanmar, and Papua New Guinea.

Kratom effect like stimulant. In cultures where the plant grows, it has been used in traditional medicine. The leaves are chewed to relieve musculoskeletal pain and increase energy, appetite, and sexual. The leaves or extracts from them are used to heal wounds and as a local anesthetic. Extracts and leaves have been used to treat coughs, diarrhea, and intestinal infections. Kratom is often used by workers in laborious or monotonous professions to stave off exhaustion as well as a mood enhancer and/or painkiller. In Thailand, kratom was “used as a snack to receive guests and was part of the ritual worship of ancestors and gods.The herb is very bitter and is generally combined with a sweetener.