Marijuana is a drug. THC (∆9-tetrahydrocannabinol) is the primary active ingredient in marijuana. After smoking or oral administration, the major psychoactive compound, tetrahydrocannabinol (THC) is extensively metabolized before excretion. The main metabolite excreted in the urine is 11-nor- ∆9-THC-9-COOH.
This drug under prescription reduce the nauseas and vomiting in patients undergo chemotherapy, stimulate appetite at cancer and HIV patients, reduce nervous chronic pain and treatment of multiple sclerosis.

The H&R THC card is lateral flow, one-step immunoassay for the qualitative detection of marijuana in human urine at the following cut-off concentrations:
THC   11-nor- ∆9-THC-9-COOH  50ng/mL

This assay provides only a preliminary analytical test result. A more specific alternative chemical method must be used in order to obtain a confirmed analytical result. Gas chromatography/mass spectrometry (GS/MS) has been established as the preferred confirmatory method. Clinical consideration and professional judgment should be applied to any drug test result, particularly when preliminary positive results are indicated.