Tetrahydrocannabinol (THC)

Tetrahydrocannabinol (THC)

Tetrahydrocannabinol (THC) is the principal psychoactive cannabinoid in cannabis, most commonly referring to the delta-9-THC isomer. It acts primarily as a partial agonist at CB1 receptors in the central nervous system and is responsible for euphoria, altered perception, and many of the drug's intoxicating effects.

Effects

  • Psychoactive: Euphoria, altered time perception, relaxation or anxiety depending on dose and set/setting.
  • Physiological: Increased heart rate, appetite stimulation, dry mouth, and conjunctival injection (red eyes).

Clinical and forensic notes

  • Potency trends: Illicit cannabis potency (THC concentration) has increased over recent decades, sometimes altering harm profiles.
  • Medical uses: THC-containing medicines (or THC+CBD combinations) are used for some indications (e.g., nausea from chemotherapy, spasticity) in jurisdictions where approved.

Risks

  • High-dose and frequent THC exposure correlates with higher rates of dependence and adverse psychiatric outcomes in vulnerable people.

See also