Tetrahydrocannabinol (THC) What is it?

What is tetrahydrocannabinol (THC)

tetrahydrocannabinol (THC) 

“THC” redirects here. For other uses, see THC (disambiguation).
Tetrahydrocannabinol (THC)
INN: dronabinol
Systematic (IUPAC) name
Clinical data
Trade names Marinol
License data
  • US: C (Risk not ruled out)
8–10% (Relatively low risk of tolerance)[1]
Routes of
Orally, local/topical, transdermal, sublingual, inhaled
Legal status
Legal status
Pharmacokinetic data
Bioavailability 10–35% (inhalation), 6–20% (oral)[3]
Protein binding 97–99%[3][4][5]
Metabolism Mostly hepatic by CYP2C[3]
Biological half-life 1.6–59 h,[3] 25–36 h (orally administered dronabinol)
Excretion 65–80% (feces), 20–35% (urine) as acid metabolites[3]
CAS Number 1972-08-3 Yes
ATC code A04AD10 (WHO)
PubChem CID 16078
DrugBank DB00470 Yes
ChemSpider 15266 Yes
UNII 7J8897W37S Yes
ChEBI CHEBI:66964 
Synonyms  (6aR,10aR)-delta-9-tetrahydrocannabinol
Chemical data
Formula C21H30O2
Molar mass 314.469 g/mol
Specific rotation −152° (ethanol)
Physical data
Boiling point 157 °C (315 °F) [7]
Solubility in water 0.0028,[6] (23 °C) mg/mL (20 °C)
 Yes (what is this?)  (verify)

Tetrahydrocannabinol (THC, dronabinol by INN), or more precisely its main isomer (−)-trans9-tetrahydrocannabinol, is the principal psychoactive constituent (or cannabinoid) of cannabis. It can be an amber or gold colored glassy solid when cold, which becomes viscous and sticky if warmed.

Like most pharmacologically-active secondary metabolites of plants, THC in Cannabis is assumed to be involved in self-defense, perhaps against herbivores.[8] THC also possesses high UV-B (280–315 nm) absorption properties, which, it has been speculated, could protect the plant from harmful UV radiation exposure.[9][10][11]

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.[12] Cannabis as a plant is scheduled by the Single Convention on Narcotic Drugs (Schedule I and IV).

A pharmaceutical formulation is available by prescription in the U.S. and Canada under the brand name Marinol.