tetrahydrocannabinol

tetrahydrocannabinol (THC), active constituent of marijuana and hashish that was first isolated from the marijuana plant (Cannabis sativa) and synthesized in 1965. Tetrahydrocannabinol (THC) is present in all parts of both the male and female cannabis plants but is most concentrated in the resin (cannabin) in the flowering tops of the female. See also medical cannabis.

THC’s effects vary, depending upon the strength and amount consumed, the presence and potency of other cannabinoids (such as cannabidiol [CBD]), the setting in which it is taken, and the experience of the user. Psychological effects tend to predominate, with the user commonly experiencing a mild euphoria. Alterations in vision and judgment result in distortions of time and space. Acute intoxication may occasionally induce visual hallucinations, anxiety, depression, extreme variability of mood, paranoid reactions, and psychoses lasting four to six hours. Physical effects include reddening of the eyes, dryness of the mouth and throat, moderate increase in the rapidity of the heartbeat, tightness of the chest (if the drug is smoked), drowsiness, unsteadiness, and muscular incoordination.

In the late 1980s researchers discovered a receptor for THC and THC-related chemicals in the brains of certain mammals, including humans. This finding indicated that the brain naturally produces a THC-like substance that may perform some of the same functions that THC does. Such a substance subsequently was found and named anandamide, from the Sanskrit ānanda (“bliss”).

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marijuana: Tetrahydrocannabinol (THC)

Medical research in the late 20th and early 21st centuries revealed various therapeutic effects of marijuana and THC. They were found to be useful in lowering internal eye pressure in persons suffering from glaucoma and in alleviating nausea and vomiting caused by chemotherapeutic drugs used to treat cancer patients and those with AIDS. THC also has been found to reduce the muscle pain associated with multiple sclerosis and to prevent epileptic seizures in some patients.

Delta-8-tetrahydrocannabinol (THC) is chemically related to delta-9-THC, the primary psychoactive compound in cannabis products, but has milder psychoactive effects. Within cannabis plants, only very small amounts of delta-8-THC are produced, far less than delta-9-THC. Delta-8-THC is thought to have some potential therapeutic benefits, though a lack of scientific evidence and regulatory oversight has raised concerns about safety and quality.