In some form, cannabis is now legal in 33 states including 10 that allow adult recreational use. This emerging and quickly growing market has sparked a new breed of cannabis entrepreneurs pioneering innovative cannabis-infused products like the Keurig-style vape pods from CannaKorp, a Massachusetts-based company recently acquired by the Target Group.
But when shopping for cannabis, whether it’s recreational or medicinal, most consumers probably aren’t considering bioavailability. Bioavailability is a term used to describe the pharmacokinetic properties of a drug. It’s a subcategory of absorption and corresponds to the proportion of a dose that reaches systemic circulation.
In the case of cannabis, the active compounds are cannabinoids like THC and CBD. But depending on how you choose to consume cannabis, you could be absorbing less than 10% of the total cannabinoids in a given dose. Let’s take a look at some of the factors that affect cannabinoid bioavailability and how it can be increased.
The Method Matters
By definition, drugs administered intravenously have a bioavailability of 100%. However, other methods of administration tend to decrease a drug’s bioavailability. Individual metabolic variations play a role, but the method you choose to ingest cannabis will have the largest effect on how well THC and CBD are able to reach your circulatory system.
Smoking and vaping are one of the more efficient methods in terms of bioavailability. One study found that smoked THC has an average bioavailability of 30% while, in contrast, orally ingested THC ranges from 4% to 12%. The results for CBD are similar when comparing smoking to oral ingestion.
Increasing Cannabinoid Absorption
Smoking appears to be the most efficient method for absorbing cannabinoids. However, many people choose to avoid smoking for health reasons and oral administration is by far the preferred method in clinical settings.
The reduced bioavailability of cannabinoids when taken orally is not a new phenomenon. Pharmacologists are familiar with the first pass effect when the concentration of an orally administered drug is greatly reduced before it reaches systemic circulation due to enzymatic breakdown and other factors. While this phenomenon can actually enhance the effects of THC, the same isn’t true of CBD.
So is there a way to improve bioavailability when taking cannabis, particularly CBD, orally in the form of edibles or extract oils?
One research group found that orally co-administering cannabinoids with lipids or fats can significantly increase their intestinal transport in rats. Similarly, pharmacokinetic studies exploring the effects of CBD in patients found that CBD oil consumed with a high-fat meal increased the drug’s bioavailability up to fivefold.
A more high-tech approach uses a nanoemulsion, a solution containing evenly distributed microscopic, insoluble particles to reduce surface tension and stabilize the mixture. CBD nanoemulsions increased CBD bioavailability in rats by 20% and could represent a commercially viable way of increasing the absorption and quickening the onset of CBD.
Closing Thoughts
Bioavailability should be an important factor when considering cannabis dosage, especially in the case of CBD-dominant products taken orally like edibles and oil extracts.
But first and foremost, cannabis consumers and businesses developing new products need to know the overall cannabinoid potency. Encore Labs is an ISO/IEC 17025:2017 accredited lab that offers cannabinoid profiling and comprehensive cannabis testing.