tetrahydrocannabinolic

Tetrahydrocannabinolic, usually referring to delta-9-tetrahydrocannabinol (Δ9-THC), is the primary psychoactive constituent of cannabis. It is a phytocannabinoid produced in the resin glands of the female cannabis plant and is among the most abundant cannabinoids in Cannabis sativa and Cannabis indica. The compound is lipophilic and can accumulate in fatty tissues.

Its pharmacology involves partial agonism at cannabinoid receptors CB1 and CB2, with CB1–mediated effects in the central nervous system contributing to psychoactivity, euphoria, altered perception, time distortion, and impairment of motor function. CB2 activity modulates inflammatory and immune responses. THC also interacts with other receptor systems and produces analgesic, antiemetic, and appetite-stimulating effects at therapeutic doses.

THC is produced from tetrahydrocannabinolic acid (THCA) through decarboxylation when cannabis is heated (smoked, vaporized, cooked). Pharmacokinetics vary by route: inhalation yields rapid systemic exposure with peak plasma levels within minutes; oral ingestion yields slower, variable absorption with a delayed peak. Hepatic metabolism primarily forms 11-hydroxy-THC, then 11-nor-9-carboxy-THC (THC-COOH), which is excreted in urine and feces. The elimination half-life is influenced by body fat, usage patterns, and frequency of exposure.

Medicinally, THC and its synthetic analogs have been used for antiemetic effects in chemotherapy, as an appetite stimulant in conditions such as AIDS-related wasting, and for chronic pain in some contexts. The U.S. market includes dronabinol and nabilone. Therapeutic use is subject to regulatory approvals and varies by jurisdiction. Recreational use raises safety concerns, including cognitive impairment, risk of dependence, and potential psychiatric effects in vulnerable individuals.

Legal status ranges from illegal to regulated medical or recreational use, with many countries enacting restrictions and licensing schemes for cannabis products containing THC.