Which psychoactive compound in marijuana (cannabis) produces the primary intoxicating effects and is detectable in urine drug testing?

Tetrahydrocannabinol (THC) is the primary psychoactive constituent of cannabis (marijuana). It acts on CB1 and CB2 cannabinoid receptors in the brain and peripheral tissues, producing euphoria, altered perception, and increased appetite. In dentistry, THC use is relevant because: cannabis use increases caries risk (dry mouth, sugar-containing edibles, acidic beverages), chronic use is associated with periodontal disease and increased candida infection, cannabis smoke contains carcinogens increasing oral cancer risk, and THC has drug interactions with sedatives and analgesics. Cannabidiol (CBD) does not produce intoxication and is not typically screened in standard urine drug tests.