Bioavailability

Bioavailability refers to how much of a substance is absorbed into the body of a living system and is thus able to have an active effect. The availability of a substance you put in your body is closely tied to the method of consumption. A substance generally has a of 100% when administered intravenously, but is generally lower when taken in other ways. The bioavailability of the THC in cannabis can vary between 2-56% when smoked. For instance, if smoking has a bioavailability of 50%, then when you smoke a gram of cannabis only half of the active THC in that gram will enter your bloodstream. Bioavailability tends to be lower with oral ingestion because it has to pass through the gastrointestinal tract and the liver before entering the bloodstream.