THC (9-tetrahydrocannabinol) is the primary active ingredient in cannabinoids (marijuana). When ingested or smoked, it produces euphoric effects. Users have impairment of short-term memory and THC use slows learning. Also, it may cause transient episodes of confusion, anxiety, or even frank toxic delirium. Long term, relatively heavy use may be associated with behavioral disorders. The peak effect of smoking THC occurs in 20-30 minutes and the duration is 90-120 minutes after one cigarette. Elevated levels of urinary metabolites are found within hours of exposure and remain detectable for 3-10 days after smoking. The main metabolite excreted in the urine is 11-nor- 9-tetrahydrocannabinol-9-carboxylic acid. The THC (Marijuana) drug test marijuana is based on the principle of the highly specific immunochemical reactions between antigens and antibodies, which are used for the analysis of specific substances in biological fluids. The cutoff of the test is 50 ng/ml of THC. It is the same as the SAMHSA (The Substance Abuse and Mental Health Services Administration) recommended assay cutoff. The THC test kit contains the following items to perform the assay: