Understanding THC and CBD

As a medical cannabis patient, the amount of new information can feel overwhelming. There are a lot of new terms and concepts, and it is important to have an understanding of these. A solid foundational knowledge allows for better communication with doctors, pharmacists, and other health care practitioners. Let’s take a look at some of the key elements.

What are THC and CBD?

THC (delta-9-tetrahydrocannabinol) and CBD (cannabidiol) are produced by the cannabis plant. They are the main active ingredients found in cannabis, and belong to a group of molecules called cannabinoids¹. Interestingly, they are not naturally produced by cannabis, instead they are formed through a process known as decarboxylation ².

In nature, THC and CBD exist as acidic versions of themselves called THCA and CBDA, and when  cannabis is heated through smoking, vaporizing, cooking or baking the “acidic” portion of the THCA and CBDA molecule (known as a carboxyl) is removed,  forming THC and CBD respectively ².

It is important to note that our ingestible oils and vape concentrates come pre-activated which means they do not need to be activated through heating before use.

How are Cannabinoids interacting with the Body?

Over 100 different types of cannabinoids are produced by the cannabis plant ¹, with THC and CBD being the most abundant. Although THC and CBD are both cannabinoids, when consumed they act very differently in the body.

THC is the main cannabinoid responsible for the feeling of intoxication, commonly known as a “high” ³. THC interacts with the body’s endocannabinoid system (ECS) by activating cannabinoid receptors called CB₁ and CB₂. The ECS is an ancient signaling system and is responsible for helping regulate cognitive and physiological processes, memory, fertility, mood and appetite, among other functions ⁴. THC activates these receptors by binding to them in a manner that is similar to a lock and key, when this occurs changes happen in the body .

THC activates cannabinoid receptors in the body through a lock and key mechanism.

CBD is a non-intoxicating cannabinoid ^1,3, although when vaporized at high doses (400 mg) one study found CBD to be mildly intoxicating . Similar to THC, CBD interacts with the ECS, however it does so in a different manner. As a result, CBD is thought to help counter some of the unwanted side-effects felt from THC such as anxiety ^3,6,7. In addition to the ECS, CBD also exerts its effects in the body by interacting with other signaling pathways ⁸.

Does the Ratio of THC to CBD matter?

Different cannabis products have different ratios of THC to CBD. Some are THC dominant, others CBD dominant, and still others are more balanced in their ratio. But what exactly does this mean?

Understanding the differences between these product types is important as the ratio of THC to CBD will influence the effectiveness and risk of encountering unwanted side effects from each product.

DID YOU KNOW? CBD dominant products still contain small amounts of THC. This means individuals working in worksafe positions may still test positive for THC during random drug screening and should speak with their employer before using cannabis ⁹.

How to Help Prevent Unwanted Side-Effects?

In general, unwanted side effects from cannabis (i.e. dizziness, increased heart rate, and fatigue) are due to the amount of THC consumed ^3,10. Interestingly, studies are beginning to emerge which show that CBD can decrease unwanted side effects caused from THC³. Although further research is still needed to understand this interaction, Canada’s lower risk cannabis use guidelines recommends using products which contain lower amounts of THC or a higher ratio of CBD to THC (i.e. balanced or CBD dominant products)¹¹.

Selecting the Right Ratio can help Predict Therapeutic Effects

Both THC and CBD contribute to the therapeutic effects of cannabis. The type and ratio of cannabinoids present in a product can help to determine its benefits. Research indicates that THC dominant, CBD dominant and THC:CBD balanced products can be helpful for treating certain diseases and/or symptoms including the following:

* This table has been provided for informational purposes only and is not intended to be used for product selection purposes.

When considering using Cannabis for medicinal purposes it is important to first speak with your doctor so that a proper assessment and diagnosis can be made. It is also important to let your doctor know which types of medication you are taking, as THC and CBD can interact with certain drugs.

References

1. Health Canada (2019) About Cannabis. https://www.canada.ca/en/health-canada/services/drugs-medication/cannabis/about.html
2. Solymosi, K., & Koefalvi, A. (2017). Cannabis: a treasure trove or pandora’s box?. Mini reviews in medicinal chemistry, 17(13), 1223-1291. https://www.ncbi.nlm.nih.gov/pubmed/27719666
3. Health Canada (2019) What you need to know if you choose to consume cannabis. Electronic document, https://www.canada.ca/en/health-canada/services/drugs-medication/cannabis/resources/what-you-need-to-know-if-you-choose-to-consume-cannabis.html, accessed February 2020.
4. Health Canada (2018) Information for Health Care Professionals. https://www.canada.ca/content/dam/hc-sc/documents/services/drugs-medication/cannabis/information-medical-practitioners/information-health-care-professionals-cannabis-cannabinoids-eng.pdf
5. Solowij, N., Broyd, S., Greenwood, L. M., van Hell, H., Martelozzo, D., Rueb, K., … & Murray, R. (2019). A randomised controlled trial of vaporised Δ 9-tetrahydrocannabinol and cannabidiol alone and in combination in frequent and infrequent cannabis users: acute intoxication effects. European archives of psychiatry and clinical neuroscience, 269(1), 17-35.https://www.ncbi.nlm.nih.gov/pubmed/30661105
6. Robson, P. J. (2014). Therapeutic potential of cannabinoid medicines. Drug testing and analysis, 6(1-2), 24-30. https://onlinelibrary.wiley.com/doi/abs/10.1002/dta.1529
7. Zuardi, A. W., Shirakawa, I., Finkelfarb, E., & Karniol, I. G. (1982). Action of cannabidiol on the anxiety and other effects produced by Δ 9-THC in normal subjects. Psychopharmacology, 76(3), 245-250. https://link.springer.com/article/10.1007/BF00432554
8. White, C. M. (2019). A review of human studies assessing cannabidiol’s (CBD) therapeutic actions and potential. The Journal of Clinical Pharmacology, 59(7), 923-934.
9. Spindle, T. R., Cone, E. J., Kuntz, D., Mitchell, J. M., Bigelow, G. E., Flegel, R., & Vandrey, R. (2019). Urinary Pharmacokinetic Profile of Cannabinoids Following Administration of Vaporized and Oral Cannabidiol and Vaporized CBD-Dominant Cannabis. Journal of analytical toxicology. https://academic.oup.com/jat/advance-article-abstract/doi/10.1093/jat/bkz080/5611263
10. MacCallum, C. A., & Russo, E. B. (2018). Practical considerations in medical cannabis administration and dosing. European journal of internal medicine, 49, 12-19.
    https://www.sciencedirect.com/science/article/abs/pii/S0953620518300049
11. Fischer, B., Russell, C., Sabioni, P., van den Brink, W., Le Foll, B., Hall, W., Rehm, J. & Room, R. (2017). Lower-Risk Cannabis Use Guidelines (LRCUG): An evidence-based update. American Journal of Public Health, 107 (8). DOI: 10.2105/AJPH.2017.303818. https://www.camh.ca/-/media/files/pdfs—reports-and-books—research/canadas-lower-risk-guidelines-cannabis-pdf.pdf
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16. Flachenecker et al. (2014) Nabiximols (THC/CBD Oromucosal Spray, Sativex ®) in clinical practice -results of a multicenter non-interventional study (Move 2) in patients with multiple sclerosis spasticity. European Neurology 71:271-279.
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