You are now familiar with the basics of the endocannabinoid system and its interaction with the phytocannabinoids CBD and ∆-9-THC. Although CBD and ∆-9-THC are the most prevalent phytocannabinoids, they are not the only to consider in selecting the particular chemovar (the specific chemical composition of cannabinoids and terpenes present in a particular cannabis specimen) of medical cannabis most appropriate for your conditions. Next is another version of tetrahydrocannabinol.

Phytocannabinoid: ∆-8-THC ∆-8-THC is a tetrahydrocannabinol which has a subtle difference in chemical structure and more pronounced clinical differences than ∆-9-THC. Chemically, the difference is a movement of a double bond from the 8th carbon atom to the 9th carbon atom in the molecule. This change in structure makes the understood effects of ∆-8-THC on the endocannabinoid system somewhat different than that of the more familiar ∆-9-THC. Like ∆-9-THC, the ∆-8-THC variant is a partial agonist of the CB1 and perhaps CB2 receptors. It is useful for treating poor appetite, pain, inflammation, anxiety, depression and has anticancer properties. As an anti-nausea medication, this cannabinoid has been shown to be as much as 200 times more potent than ∆-9-THC. The presence of ∆-8-THC in a particular chemovar makes it the preferred treatment for nausea and vomiting.

∆-8-THC does cause euphoric effects; however, they are reported to be about 25% less intense than ∆-9-THC and be less impairing to thought processes, less likely to produce anxiety and cause less "fogginess". It is usually tolerated at higher doses than ∆-9-THC with respect to the impairing euphoric effects. This makes it a good choice for patients who find these side effects of ∆-9-THC limiting their dose of tetrahydrocannabinol and possibly their response to treatment. As with ∆-9-THC, the co-administration of CBD will further decrease the psychoactive effects of ∆-8-THC.

The ∆-8-THC variant of tetrahydrocannabinol is usually expressed in relatively low amounts in certain chemovars. From the standpoint of nausea treatment, even a low expression of the cannabinoid will make it effective, owing to its very high potency in relieving this symptom. The low quantities present and the dominance of ∆-9-THC limit its use as a primary tetrahydrocannabinol. Currently, some cultivators have developed and are continuing to refine extraction and conversion techniques to isolate ∆-8-THC in high concentrations not found in most cannabis species.

Back to the Big Picture

∆-8-THC, like ∆-9-THC and CBD, is just one piece of the cannabinoid puzzle. A small piece compared to the two big players in the phytocannabinoid world, but one with a specific effectiveness now. For patients with nausea, poor appetite or cachexia (weight loss), ∆-8-THC alone can be very effective. For most conditions, it will only offer a partial response. It is the combination of and relative ratios of the individual cannabinoids and terpenes working together that produce the desired response.

As isolates of ∆-8-THC continue to be developed and chemovars with higher levels of the cannabinoid are cultivated, it will become more widely available and the properties of ∆-8-THC can be better exploited.

Chemovar Considerations

After the appropriate THC to CBD ratios have been selected for your condition, the other cannabinoids are next to consider. If you are a patient with intermittent nausea and vomiting, the addition of a separate strain with ∆-8-THC administered by inhalation will likely be just what you need. If you feel some anxiety or impairment with doses of ∆-9-THC adequate to control symptoms, a strain containing ∆-8-THC and CBD (or additional CBD by tincture or flower) can decrease these symptoms. When isolates of ∆-8-THC become available, you may consider using it as your main tetrahydrocannabinol source, and add other additional cannabinoids to "create" the chemovar most appropriate for you.

Next Up: A rare, "primitive" tetrahydrocannabinol that is being searched for the world over.

Brian Nichol MD
Cannabis Expert