THC (tetrahydrocannabinol)
The primary intoxicating cannabinoid in cannabis, first isolated in 1964.
Tetrahydrocannabinol is the compound responsible for the intoxicating effect of cannabis. It was first isolated and described in 1964 by the group led by Raphael Mechoulam at the Hebrew University of Jerusalem — the work that opened modern cannabinoid science.
THC content is also the line that separates hemp from other cannabis in law. Cultivars grown for fibre, seed or CBD are bred for low THC; others are bred for high THC.
Research increasingly suggests THC and CBD act differently together than either does alone — the effect described below under entourage effect.