When you get a drug test they normally use a urine or blood sample and check for the presence of THC (Tetrahydrocannabinol)   THC-COOH, and THC-11-oic acid are formed in the liver after the body has consumed cannabis and it is these chemicals that are tested when you go for a blood or urine test. THC-COOH doesn’t have much cross reactivity to the other non psychoactive cannabinoids such as CBD (cannabidiol), CBG (cannabigerol) or CBN (cannabinol), which means if you have taken CBD Hemp oil you probably won’t get a positive result on any drug test.   Theoretically it is possible if you are taking very large doses of CBD oil (above 1000-2000mg per day) due to the minute traces of THC that could build up over time. Due to differing body weight, metabolic rate and other lifestyle factors it’s possible that cbd oil containing as little 0.3% THC could show up in swabs, blood or urinalysis. Patients must determine for themselves if the severity of their condition outweighs this possibility.