Tetrahydrocannabinol (colloquially known as THC) is the main psychoactive constituent of cannabis. This organic compound can be used to treat diseases and conditions by inducing relaxation, stimulating appetite and altering visual, auditory and olfactory senses. The compound was first isolated by Israeli scientists Raphael Mechoulam, Yechiel Gaoni and colleagues in 1964 at the hebrew-university-of-jerusalem.