Tetrahydrocannabinol (THC) is one of the major active cannabinoids found in cannabis. It is the main compound responsible for the psychoactive effects of cannabis, including changes in mental processes (e.g., thoughts, mood, and perception) that cause the feeling of being “high”.[1] While THC is found naturally in cannabis in combination with many other active compounds, like cannabidiol (CBD), some supplements and prescription medications contain isolated THC or synthetic THC analogs, which will be the focus of this page.