At first glance, its easy for a patient to choose their medical cannabis products based solely on the amount of cannabinoids contained in each one. However, what really matters is how much of said cannabinoids actually make it into the patient’s system. Bioavailability: “the degree and rate at which a substance (such as a drug) is absorbed into a living system or is made available at the site of physiological activity” –Merriam-Webster
100% bioavailablity can only be achieved through intravenous (IV) administration of a compound. Cannabinoids are hardly ever administered through an IV. The most common routes for administration are via the lung tissue, mouth tissue, GI tract, or the skin. Saving you the little details, the sections below will outline these various routes for consumption, in order, and their rates of bioavailability.
Inhalation, vaporization/vaping:
Products – Dried cannabis flower
Absorption site – Lung tissues
50% – 80% Bioavailability
10mg dose: 5mg – 8mg will be absorbed within 0-5 minutes.
NOTE: Although dabs, e-cigarette style pens, and other concentrates may produce vapor, we will advise against the use of those products except in certain circumstances.
Oral Absorption:
Products – drops, sprays, lozenges, dissolving strips
Absorption site – Mouth tissues
40% – 50% Bioavailability
10mg dose: 4mg – 5mg will be absorbed within 10-40 minutes.
NOTE: Bioavailability range has to do with concentrations of veins in the mouth, relative blood flow, as well as conditions inside the mouth.
Inhalation, smoking, pipes:
Products – Dried cannabis flower
Absorption site – Lung tissues
50% Bioavailability
10mg dose: 5mg will be absorbed within 0-10 minutes.
Inhalation, smoking, cannabis cigarettes:
Products – Dried cannabis flower, pre-rolled joints
Absorption site – Lung tissues
30% Bioavailability
10mg dose: 3mg will be absorbed within 0-10 minutes.
Edibles/eating:
Products – Pills, tarts/mints, cookies, gummies, brownies, etc.
Absorption site – GI (gastro-intestinal) tract
4% – 20% Bioavailability
10mg dose: 0.4mg – 2mg will be absorbed within 30-90 minutes.
NOTE: A wide range of bioavailability is due to large variations in gut conditions, even when given to the same person on a different day (e.g. time of last meal, fat content of last meal, illness, time of day, etc.).
Topicals:
Products – Lotions, salves, massage oils, etc.
Absorption site – Skin near affected area
5% – 10% Bioavailability
10mg dose: 0.5 – 1mg will be absorbed (locally) within 2-3 minutes.
Further reading:
SafeAccessNow.com
RoyalQueenSeeds.com
Medium.com
| Mode | Entry Point | Bioavailability | Rate |
| Vapor | Lungs | 50% – 80% | 0-10min |
| Pipe | Lungs | 50% | 0-10min |
| Oral | Mouth | 40%-50% | 10-40min |
| Joint | Lungs | 30% | 0-10min |
| Edible | GI tract | 4%-20% | 30-90min |
| Topical | Skin | 5%-10% | 2-3min |