Tetrahydrocannabinol (THC) is the main psychoactive cannabinoid in cannabis. It acts as a partial agonist at central cannabinoid (CB1) receptors, producing euphoria, altered perception, relaxation, analgesia and increased appetite. THC has therapeutic uses (e.g., nausea, pain) but can impair cognition and motor skills and carries risks of tolerance, dependence and psychiatric effects, especially with high doses or frequent use.

Tetrahydrocannabinol (THC) produces psychoactive effects such as euphoria, relaxation, altered time perception, and impaired memory, attention and coordination. It can increase heart rate, appetite, dry mouth and red eyes, and may relieve pain, nausea, or spasticity. Acute adverse effects include anxiety, paranoia and impaired driving. With frequent use there is risk of dependence, cognitive impairment and, in susceptible individuals, increased risk of psychosis; respiratory harms occur with smoking.

THC can be detected in urine for varying periods: single use about 1–3 days; occasional users 3–7 days; regular users up to 10–30 days; chronic heavy users up to 30–90 days. Detection depends on dose, metabolism, body fat, hydration and testing sensitivity. Urine tests measure THC metabolites (THC‑COOH), not active THC.

Yes—tetrahydrocannabinol (THC) is a naturally occurring phytocannabinoid produced by Cannabis plants, primarily stored as an acidic precursor (THCA) that converts into psychoactive THC when heated (decarboxylation). THC can also be manufactured synthetically for research or medical use. Its effects result from interaction with the body's endocannabinoid receptors. Potency and composition vary by strain and processing.

Tetrahydrocannabinol or THC is not highly lethal at typical recreational or medicinal doses, but it can be toxic. High or unintentional doses—especially in children—cause severe agitation, hallucinations, vomiting, rapid heart rate and breathing problems, sometimes requiring emergency care. Long-term use raises risks of dependence, cognitive impairment and psychiatric disorders in vulnerable people. Fatalities from THC alone are very rare.

Delta-9-THC is the main natural psychoactive cannabinoid, but potency varies. High‑purity cannabis concentrates (distillates, dabs, THCA/crystalline “diamonds”) can reach roughly 80–99% THC. Synthetic cannabinoids — different chemical compounds sold as “spice/K2” — act as much stronger full agonists at cannabinoid receptors and are far more potent and unpredictable, carrying a higher risk of severe toxicity and harm.