EXPLANATION
Tetrahydrocannabinol (
THC) is one of at least 113
cannabinoids identified in
cannabis. THC is the principal
psychoactive constituent of cannabis. With chemical name
(−)-trans-Δ⁹-tetrahydrocannabinol, the term
THC also refers to cannabinoid
isomers.
Like most pharmacologically-active
secondary metabolites of plants, THC is a
lipid found in cannabis,
[9] assumed to be involved in the plant's
self-defense, putatively against
insect predation,
ultraviolet light, and
environmental stress.
[10][11][12]
THC, along with its double bond isomers and their
stereoisomers[13], is one of only three cannabinoids scheduled by the UN
Convention on Psychotropic Substances (the other two are
dimethylheptylpyran and
parahexyl). It was listed under Schedule I in 1971, but reclassified to Schedule II in 1991 following a recommendation from the
WHO. Based on subsequent studies, the WHO has recommended the reclassification to the less-stringent Schedule III.
[14] Cannabis as a plant is scheduled by the
Single Convention on Narcotic Drugs (Schedule I and IV). It is specifically still listed under Schedule I by US federal law
[15] under the
Controlled Substances Act for having "no accepted medical use" and "lack of accepted safety". However,
dronabinol is a synthetic form of THC approved by the
FDA as an appetite stimulant for people with
AIDS and
antiemetic for people receiving
chemotherapy.
[16] The
pharmaceutical formulation dronabinol is an oily
resin provided in
capsules available by
prescription in the United States, Canada, Germany, and New Zealand.
