Cannabis and cannabinoid products can be consumed a variety of ways, each with its own pros and cons. Every consumption method features a unique level of bioavailability, which describes what percentage of the administered compound is available to be used by the body. Of the cannabinoids that are bioavailable, approximately < 1% actually make it to the brain. Learn more about the various routes of administration, or consumption methods, below.
Pulmonary (Smoking/Vaporizing)
When Cannabis flowers or extracts are smoked or vaporized, the cannabinoids enter the lungs and fill the lungs' alveoli, which are the centers of gas/blood exchange in the lungs. The cannabinoids pass into blood vessels in the alveoli and are then carried to the brain and throughout the body by the blood. Approximately 30% of cannabinoids present in smoked or vaporized Cannabis pass through to the smoke or vapor when heated and inhaled.
Bioavailability: 2 - 60%; 30% on average
Onset: ~30 seconds
Bioavailability: 2 - 60%; 30% on average
Onset: ~30 seconds
Oral (Edibles)
The body processes Cannabis products much differently when they are eaten versus when they are consumed through other means. When Cannabis products are eaten, the must be metabolized before the cannabinoids enter the blood stream. A result of this process is that THC is converted into 11-OH-THC, which is thought to be approximatley four (4) times as potent as THC. It can take anywhere from 15 minutes to 2 hours or more for the body to process edibles.
Bioavailability: 4 - 12%; Absorption highly variable
Onset: 15 minutes to 2 hours
Bioavailability: 4 - 12%; Absorption highly variable
Onset: 15 minutes to 2 hours
Oromucosal/Sublingual (Drops, Mouth Sprays)
The mouth contains a mucosal layer similar to that found in the lungs or nasal cavities, which allows cannabinoids to pass through to blood vessels that light beneath. For this reason, sublingual cannabinoid products do not undergo metabolism and avoid the conversion of THC to the more potent 11-OH-THC. In addition, sublingual consumption leads to a quicker onset of effects compared to oral administration.
Bioavailability: 15 - 25%
Onset: 2 - 10 minutes
Bioavailability: 15 - 25%
Onset: 2 - 10 minutes
Epicutaneous and Transdermal (Topicals)
Epicutaneous administration refers to products applied to the skin. The various parts of the skin exhibit cannabinoid receptors, allowing for direct, local pharmacological effects when topical cannabinoid products are applied to the skin. In addition, blood vessels are accessible in the dermal layer of the skin, though many cannabinoid products cannot penetrate deeply enough into the skin to reach the dermal layer. Transdermal products feature special assistive compounds that help the cannabinoids (and other present compounds) penetrate the skin deeply to reach the blood vessels in the dermal layer.
It is a false assumption that Cannabis topicals will not produce intoxicating effects or show up on drug tests.
It is a false assumption that Cannabis topicals will not produce intoxicating effects or show up on drug tests.
Less Common Methods
Other less common methods of Cannabis and cannabinoid product consumption include intravenous and intramuscular injections, vaginal and rectal suppositories, and nasal mucosal sprays.