Mitragyna speciosa

Mitragyna speciosa (commonly known as kratom) is a tropical evergreen tree in the coffee family native to Southeast Asia. M. speciosa is indigenous to Thailand, Indonesia, Malaysia, Myanmar, and Papua New Guinea, where it has been used in traditional medicines since at least the nineteenth century. Kratom has opioid properties and some stimulant-like effects. As of 2018, kratom's usefulness and safety as a therapeutic agent is unclear, since research into its use has been of poor quality. In February 2018, the United States' Food and Drug Administration (FDA) stated that there is no evidence that kratom is safe or effective for treating any condition. Some people take it for managing chronic pain, for treating opioid withdrawal symptoms, or – more recently – for recreational purposes. The onset of effects typically begins within five to ten minutes and lasts for two to five hours. Common minor side effects include nausea, vomiting, and constipation. More severe side effects may include respiratory depression (decreased breathing), seizure, addiction, and psychosis. Other side effects may include high heart rate and blood pressure, trouble sleeping, and, rarely, liver toxicity. When use is stopped, withdrawal symptoms may occur. Deaths have occurred with kratom both by itself and mixed with other substances. Over 18 months in 2016 and 2017, 152 overdose deaths involving kratom were reported in the United States, with kratom as the primary overdose agent in 91 of the deaths. Nine kratom-related deaths occurred in Sweden in 2011 and 2012, all involving a mixture of kratom with other opioids. Serious toxicity is relatively rare and generally appears at high doses or when kratom is used with other substances. In the United States kratom use has increased rapidly between 2011 to 2017. As of 2018, there is growing international concern about a possible threat to public health from kratom use. In some jurisdictions, its sale and importation have been restricted, and several public health authorities have raised alerts. Kratom is a controlled substance in 16 countries and, in 2014, the FDA banned importing and manufacturing of kratom as a dietary supplement. In the United States, there is consideration to make it a Schedule I drug. Sometimes, the finished product is mixed with other psychoactive drugs, such as caffeine and codeine. In 2019, the FDA warned consumers that kratom remains unapproved for interstate commerce, may be unsafe in commercially available products, and is on an import alert which would lead to confiscation of imported supplies. Mitragyna speciosa is an evergreen tree that can grow to a height of 25 m (82 ft). Its 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 (0.08 in) long and has five lobes; the corolla-tube is 2.5–3 millimetres (0.098–0.12 in) long. M. speciosa is indigenous to Thailand, Indonesia, Malaysia, Myanmar, and Papua New Guinea. Mitragyna speciosa was first formally described by the Dutch colonial botanist Pieter Korthals in 1839, who named it as such; it was renamed and reclassified several times before George Darby Haviland provided the final name and classification in 1859.:59