Copy HTML iframe code to your website:

Social Share

Term: Tetrahydrocannabinol

  • Rate

Tetrahydrocannabinol (THC) is the principal psychoactive constituent of cannabis and one of at least 113 total cannabinoids identified on the plant. Although the chemical formula for THC (C21H30O2) describes multiple isomers, the term THC usually refers to the Delta-9-THC isomer with chemical name (−)-trans9-tetrahydrocannabinol. Like most pharmacologically active secondary metabolites of plants, THC is a lipid found in cannabis, assumed to be involved in the plant's evolutionary adaptation, putatively against insect predation, ultraviolet light, and environmental stress.

INN: dronabinol
THC 3D BS.png
Clinical data
Trade namesMarinol, Syndros
Other names(6aR,10aR)-delta-9-Tetrahydrocannabinol; (−)-trans9-Tetrahydrocannabinol; THC
License data
8–10% (Relatively low risk of tolerance)
Routes of
Oral, local/topical, transdermal, sublingual, inhaled
ATC code
Legal status
Legal status
  • AU: Unscheduled: ACT, Schedule 8 (Controlled Drug)
  • CA: Unscheduled
  • DE: Dronabinol: Anlage III, Δ9-THC: II, other isomers and their stereochemical variants: I. (Does not apply to THC as part of cannabis, which is regulated separately, see Cannabis (drug))
  • UK: Class B
  • US: Schedule II as Syndros, and Schedule III as Marinol
Pharmacokinetic data
Bioavailability10–35% (inhalation), 6–20% (oral)
Protein binding97–99%
MetabolismMostly hepatic by CYP2C
Elimination half-life1.6–59 h, 25–36 h (orally administered dronabinol)
Excretion65–80% (feces), 20–35% (urine) as acid metabolites
  • (6aR,10aR)-6,6,9-Trimethyl-3-pentyl-6a,7,8,10a-tetrahydro-6H-benzo[c]chromen-1-ol
CAS Number
PubChem CID
CompTox Dashboard (EPA)
ECHA InfoCard100.153.676 Edit this at Wikidata
Chemical and physical data
Molar mass314.469 g·mol−1
3D model (JSmol)
Specific rotation−152° (ethanol)
Boiling point155–157°C @ 0.05mmHg, 157–160°C @ 0.05mmHg
Solubility in water0.0028 mg/mL (23 °C)
  • InChI=1S/C21H30O2/c1-5-6-7-8-15-12-18(22)20-16-11-14(2)9-10-17(16)21(3,4)23-19(20)13-15/h11-13,16-17,22H,5-10H2,1-4H3/t16-,17-/m1/s1 checkY
 ☒NcheckY (what is this?)  (verify)

THC, along with its double bond isomers and their stereoisomers, 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. 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 under the Controlled Substances Act for having "no accepted medical use" and "lack of accepted safety". However, dronabinol, a pharmaceutical form of THC, has been approved by the FDA as an appetite stimulant for people with AIDS and an antiemetic for people receiving chemotherapy under the trade names Marinol and Syndros. The pharmaceutical formulation dronabinol is an oily and viscous resin provided in capsules available by prescription in the United States, Canada, Germany, and New Zealand.

Delta-9-tetrahydrocannabinol (Δ9-THC), better known as THC, is the marijuana plant's primary component for causing psychoactive effects. THC was first discovered and isolated by Israeli chemist Raphael Mechoulam in Israel in 1964. It was found that, when smoked, tetrahydrocannabinol is absorbed into the bloodstream and travels to the brain, attaching itself to the naturally occurring endocannabinoid receptors located in the cerebral cortex, cerebellum, and basal ganglia. These are the parts of the brain responsible for thinking, memory, pleasure, coordination and movement.

<< Go Back (Wiki Index)