Description
Mitragyna speciosa, kratom trees, usually grow to a height of 12–30 ft (3.7–9.1 m) tall and 15 ft (4.6 m) wide, although under the right conditions, certain species can reach up to 40 ft (12 m)–100 ft (30 m) in height. The stem is erect and branching. The leaves of the kratom tree are a dark green colour and can grow to over 7 inches (180 mm) long and 4 inches (100 mm) wide., ovate-acuminate in shape, and opposite in growth pattern.
The flowers are yellow and grow in clusters. This genus is characterized by a globular flowering head, bearing up to 120 florets each. During the flower bud stage, the developing florets are surrounded and completely covered by numerous overlapping bracteoles.
Kratom leaves are constantly being shed and being replaced, but there is some quasi-seasonal leaf shedding due to environmental conditions. During the dry season of the year leaf fall is more abundant, and new growth is more plentiful during the rainy season.
When grown outside their natural tropical habitat, leaf fall occurs with colder temperatures, around 4 degrees Celsius. The kratom tree grows best in wet, humid, fertile soil, with medium to full sun exposure, and an area protected from strong winds. There are two different strains of Kratom: White Vein and Red Vein Kratom. Though frequently located in the same areas, some places have an excess of white vein trees while others have an excess of red vein trees. For example, Borneo has more red vein Kratom and Sumatra has more white vein Kratom. Though used interchangeably by many, the two strains have different alkaloid makeups and can produce different effects.
Alkaloids
Kratom contains many alkaloids including mitragynine (once thought to be the primary active constituent), mitraphylline, and 7-hydroxymitragynine (which is currently the most likely candidate for the primary active chemical in the plant).[2] Although 7-hydroxymitragynine and mitragynine are structurally related to yohimbine and other tryptamines, their pharmacology is quite different, acting primarily as mu-opioid receptor agonists. Other active chemicals in kratom include raubasine (best known from Rauwolfia serpentina) and some yohimbe alkaloids such as corynantheidine
Effects
Kratom has been traditionally used in regions such as Malaysia, Thailand, and Indonesia, but was discovered by Western civilization during the 19th century. Besides Kratom, in Southeast Asia and the Pacific Islands it also goes by the names krathom, ithang, biak biak, ketum, kakuam, and in southern regions, thom. In these areas kratom has a history of use by laborers and in folk medicine for opium dependence and diarrhea.
Of the two main active constituents, mitragynine has been studied more thoroughly than 7-hydroxymitragynine. At lower doses, Mitragynine exhibits a yohimbine-like binding to alpha-adrenergic receptors, as well as some binding to the delta opioid receptors. As doses increase, binding to delta receptors increases, and in yet higher doses, crossover to mu receptors occurs.
7-hydroxymitragynine was only recently understood to be the main active ingredient. Limited animal research suggests it is a potent opiate agonist, but with a ceiling effect that limits the potential for respiratory depression and euphoria. No fatal overdose of kratom is known to have occurred.
One study of Thai users reported that kratom has subtle calming effects in low doses, changing over to mild stimulation in higher doses. Other anecdotal sources say that it may be a mild, caffeine-like stimulant in lower doses, but decreases the effect in higher doses, which is consistent with mitragynine's receptor binding profile. However, recent publications indicate that different alkaloids may be at work to achieve mild stimulation versus sedation: whereas higher concentrations of mitragynine are attributed to act as a anti-stimulant, 7-hydroxymitragynine appears to be a significant alkaloid for reducing stress associated with opiod craving.[2] Effects come on within five to ten minutes after use, and last for several hours, depending on individual physiognomy.The feeling has been described as subtly active, while the mind is described as calm.
Side effects, although rare, may include dry mouth, increased or decreased urination, loss of appetite, and nausea or vomiting. Possible side effects from long term use include anorexia and weight loss, insomnia, and dependence. Comprehensive scientific and clinical studies have yet to be conducted to establish the potential health risks associated with consistent long term consumption of kratom.
Kratom has recently become more known and used in Europe and North America where it has been prized for its applications to many conditions and ailments, primarily pain, depression, anxiety, and opiate withdrawal.
Opiate dependence
Although chemically similar, ibogaine and mitragynine work by different pathways, and have different applications in treatment of drug dependence. While ibogaine is intended as a treatment for opiate craving, mitragynine is used to gradually wean the user off opiates. The fact that mitragynine's mu crossover is increased by the presence of opiate drugs may be exploitable in the treatment of drug dependence, because it directs binding to where it is needed, automatically regulating the attachment ratio and modulating it towards the delta receptors over a short time. Within a few days, or months, a person dependent on opiates would stop use of opiates, and the cravings and withdrawal will be moderated by the binding of mitragynine to the delta receptors. Mitragynine could also perhaps be used as a substitution or maintenance drug to manage dependence. In Southern Thailand, many heroin users have been using kratom to break their dependence and to manage craving symptoms.
In 1999, Pennapa Sapcharoen, director of the National Institute of Thai Traditional Medicine in Bangkok said that kratom could be prescribed both for opiate dependence and to patients suffering from depression, but stressed that further research is needed. Chulalongkorn University chemists have isolated mitragynine which researchers can obtain for study.
In 1897 Ridley reported the leaves and bark of Mitragyna speciosa as a cure for the opium habit and this was quoted by Hooper (1907) In 1907 Holmes had referred to the leaves and possibly, the leaves of M. parvifolia as well, as an opium substitute. Certainly the leaves of M. speciosa have been chewed for many years under the local name 'kratom' by the native population of Thailand as a stimulant though the practice is now forbidden. As a consequence the leaves of M. javanica are frequently used as a substitute but are not considered to be as effective. The natives will also distinguish between different kratoms, for example, those with red and those with green midribs (Tantivatana, 1965).
Mitragynine was the only constituent isolated from Mitragyna speciosa it was assumed to be the physiologically active constituent having morphine-like properties, Grewel (1932) reported to be a protozoal poison but in 1933 Raymond-Hamet and Millat undertook a more critical examination and reported it to have markedly depressant properties. This was substantiated in 1934 by Masson. More recently Macko, Weisbach and Douglas (1972) reported that mitragynine possesses pain threshold elevating and antitussive properties but no addictive properties
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