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CBD Oil

Heather Bedard, C.H.E.


With ever-increasing speed, CBD products are flooding the market giving rise to a booming industry with profits estimated at over 2 billion in the year 2020. Products such as lotions, skin creams, pain-relief medications, and even shampoos line the shelves of health food stores and main-stream grocery stores alike. Consumers are attracted to the products which claim natural pain relief and the reduction of anxiety and depression among many other things. While it may seem that CBD oil is new on the health scene, CBD oil in various forms has been in use for many thousands of years. Medicinally, the first recorded use of hemp (the plant source of CBD) is in China in 2900 B.C. The ancient people found it useful for rheumatic pain, reproductive problems, and inflammatory issues. The modern era of cannabis use was introduced in the 1840’s by W.B. O’Shaughnessy, who was an Irish doctor that discovered the benefits of hemp in India and shared his findings in England.


CBD oil is an oil extracted from the plant Cannabis sativa L. found in many countries all over the world. Shortened from the official name cannabidiol, CBD is one of the main components of the cannabis plant alongside its more well-known sister compound tetrahydrocannabinol (THC). THC is known for its properties that produce feelings of relaxation, a care-free attitude, amusement, or seeing the world in a new way. Some people term this experience, a “high”. However, unlike THC, CBD oil does not cause the trademark high that THC does. This is one of the factors that drives its popularity with the general population. The exchange of terms for this plant can be confusing for people looking to determine the safety of taking CBD oil as both CBD and THC are found in the same plant. Hemp is the designation used for plants specifically bred to contain 0.3% THC or less while the term marijuana is typically used to refer to the plants containing more THC than 0.3%. At the federal level in the United States, it is illegal to grow marijuana, while hemp derived products are considered legal. Consumers should be cautioned that due to the fact that CBD and THC can come from the same plant, some CBD products may contain higher THC levels than legally allowed. Nonprescription CBD oil products are unregulated and not approved by the FDA, and many differences can occur in the chemistry of different products. This will be explored in more depth in a later section.


Although many different uses of the cannabis plant have been around for a long time, to determine the safety and efficacy of the modern uses of the plant we will look at how CBD is designed to work in the body. The internal mechanism of the body that interacts with CBD is called the endocannabinoid system (ECS). The ECS exists to interact with the body’s naturally produced cannabinoids which play a part in regulating many different bodily functions including sleep, the immune system, and appetite.[1] When a person ingests cannabinoids, these compounds interact with the same receptors as the naturally produced cannabinoids produced by the body, therefore affecting these same functions. There are two known receptors affected by cannabinoids called CB1 and CB2. These two receptors play different roles in regulating the body’s responses to outside stressors. When the body is stressed it releases endocannabinoids to bind to the receptors in the affected area, signaling the body to fix the issue. In this way the cannabinoids help to create homeostasis in the body. CB1 receptors are found primarily in the brain and CB2 receptors are found primarily in the immune system. However, these receptors are found in many other areas of the body as well in lesser quantities. The wide expression of receptors located in the body is one of the reasons that people who take CBD experience its benefits in many different areas.


It is important to note the distinction between CBD’s psychoactive properties and THC’s psychotropic abilities. The difference between the two properties is, having the ability to affect how you think and feel (psychoactive) versus your perception of reality and cognitive function (psychotropic). Technically, the ability for CBD to deliver any change in bodily function means that it does have psychoactive properties. However, scientifically, the difference comes in that CBD seems to affect the CB2 receptors resulting in physical systemic interactions while THC is preferential to the CB1 receptors found in the brain. Furthermore, CBD, if it is taken with THC, has a blocking effect causing it to mitigate some of THC’s undesirable psychotropic effects.[2]

CBD will affect different people in different ways based on any imbalances in their body and what their physical state is at the time. Interestingly enough, CBD isn’t the only outside influence on the body’s ECS. Food can also affect the ECS system. These foods include eggs, flax seeds, chia seeds and walnuts. The main difference is that these foods don’t contain the possible inclusion of THC and thus don’t require the same level of precaution.


While we can see that CBD has a clear mechanism of action, the next question is, “Is it effective?” While reports of pain reduction can be subjective, we do know that CBD oil does impact the cannabinoid receptors responsible for reducing pain.[3] This action thereby reduces inflammation and interacts with the neurotransmitters responsible for alerting the body of trauma. A good amount of research has been done outside of the United States showing the efficacy of CBD oil on various health issues. This research includes studies on cancer[4] and anxiety.[5] However, just because something shows itself to be effective in relieving symptoms doesn’t mean that it is safe or that it is actually helping to heal the issue. Many people are sounding the alarm over health concerns caused by using CBD oil and the fact that these precautions are generally not communicated to consumers.


Ingested CBD oil can interact with many different types of drugs causing a build-up of dangerous compounds normally diffused by the body. An enzyme mostly found in the liver, called CYP3A4, helps to metabolize these compounds and eliminate them from the body. CBD oil can interfere with this process causing the drug to build up in the system. This is extremely concerning as 60% of drugs on the market have interactions with the CYP3A4 enzyme putting a large portion of the population at risk. Most studies on this topic are done in vitro or on animals and more good quality studies done on humans need to be done. For this reason, care should be taken when ingesting CBD oil alongside other medications which could interact with CBD oil including anti-depressants, beta-blockers and antihistamines. Even more concerning is that CBD has been shown to affect male fertility in animals as seen in a study on cannabis and male fertility.[6] While more studies need to be done to show this conclusively in humans, consumers are not informed of this connection.


There is only one CBD drug on the market that is approved by the FDA. Its name is Epidolex and is used for treating two types of epilepsy. This drug does come with some warnings including detrimental effects on the liver. Proponents of CBD oil reiterate that Epidolex is purified, isolated, and semi-synthetic, and that consumers shouldn’t be quick to associate the side-effects of Epidolex with a CBD oil product from a minimally processed plant extract.


There don’t appear to be any long-term effects from using CBD oil. The effects typically last only as long as the compound is in the body. This is usually 3-5 hrs depending on the metabolism of the person in question, how much was consumed and the method by which it was consumed. Some people are concerned about receiving negative results on drug tests performed by their place of work. Currently, drug tests test for THC and not for CBD so this should not be an issue. However, one caveat is that CBD oil is not regulated by any agency. Because of this, differences in CBD and THC levels can occur even in products not labeled to contain THC. In this study on cannabinoid dose and label accuracy in edible medical cannabis products, the authors found that of 75 products and 45 different brands, 17% were accurately labeled, 23% were under labeled, and 60% were over labeled in THC content.[7] This means that some brands that say they do not contain THC actually do and vice versa. This fact could cause an undesirable drug test result. Furthermore, as mentioned above, this can also be a concern for people on other medications as interactions can occur. One other issue with CBD is that animal studies have shown that less than 20% is absorbed and so you may not be getting as much CBD as you think you are. While comparable studies are limited in humans, this article by an Italian research team states the actual bioavailability of CBD ingested orally as between 13% and 19% with inhalation coming in at 31%.[8] This is a difficult area to find conclusive evidence as absorption varies depending on the individual’s physical health. The extraction method of the leaf should also be considered as many solvents are considered toxic to humans. Olive oil is the most healthful, however it is not evaporated well, and one would have to consume large amounts to ingest equivalent amounts of CBD as another preparation.[9] To make things even complicated, many CBD products may be labeled full spectrum or broad spectrum. Full spectrum CBD oil will contain some THC as this preparation utilizes all the parts of the plant in small amounts. To be legal at the federal level, however, these products should contain less than 0.3% THC, but as we’ve seen, testing for this is less than satisfactory. Broad spectrum CBD oil should not contain THC at all, although it may contain many other parts of the plant. One simple way a consumer could determine a relative level of safety would be to look for a certificate of analysis or COA. But again, this analysis is not always consistent.


There is a possible cumulative effect of CBD. Many consumers use it in a variety of different products including skin care, shampoo and orally as pain relief. These effects have not been studied well enough to determine this conclusively. Does taking a dose of CBD oil in concert with your CBD oil infused hand lotion and CBD oil infused shampoo present any concern? It is still too soon to know. The time of day you take CBD oil can also affect how your body reacts and the general rule of thumb, “less is more”, should be followed. Side effects are particular to each individual and can include nausea, fatigue and irritability.


There are a few additional concerns on the uses of CBD oil that are worth mentioning. One is that people view CBD oil as a supplement and may not address the real systemic issues of the disease (i.e. blood pressure or pain). Secondly, while CBD may help some people feel less anxious, it doesn’t change the reality of their situation. Perhaps being intentional with dealing with the root cause of anxiety through counseling of some kind would be more beneficial in the long run and have longer lasting results.


While there is great potential for the future use of CBD oil, due to its lack of regulation and the inability to know what is in each bottle conclusively, I would not recommend it until that issue is resolved and more human studies are done.



-------------------- [1] Mouslech Z, Valla V. Endocannabinoid system: An overview of its potential in current medical practice. Neuro Endocrinol Lett. 2009;30(2):153-179. [2] Niesink RJ, van Laar MW. Does Cannabidiol Protect Against Adverse Psychological Effects of THC?. Front Psychiatry. 2013;4:130. Published 2013 Oct 16. doi:10.3389/fpsyt.2013.00130 [3] Darkovska-Serafimovska M, Serafimovska T, Arsova-Sarafinovska Z, Stefanoski S, Keskovski Z, Balkanov T. Pharmacotherapeutic considerations for use of cannabinoids to relieve pain in patients with malignant diseases. J Pain Res. 2018;11:837-842. Published 2018 Apr 23. doi:10.2147/JPR.S160556 [4] Barbara Romano, Francesca Borrelli, Ester Pagano, Maria Grazia Cascio, Roger G. Pertwee, Angelo A. Izzo, Inhibition of colon carcinogenesis by a standardized Cannabis sativa extract with high content of cannabidiol, Phytomedicine, Volume 21, Issue 5, 2014, Pages 631-639, ISSN 0944-7113, https://doi.org/10.1016/j.phymed.2013.11.006 [5] Zuardi AW, Rodrigues NP, Silva AL, et al. Inverted U-Shaped Dose-Response Curve of the Anxiolytic Effect of Cannabidiol during Public Speaking in Real Life. Front Pharmacol. 2017;8:259. Published 2017 May 11. doi:10.3389/fphar.2017.00259 [6] Payne KS, Mazur DJ, Hotaling JM, Pastuszak AW. Cannabis and Male Fertility: A Systematic Review. J Urol. 2019;202(4):674-681. doi:10.1097/JU.0000000000000248 [7] Vandrey R, Raber JC, Raber ME, Douglass B, Miller C, Bonn-Miller MO. Cannabinoid Dose and Label Accuracy in Edible Medical Cannabis Products. JAMA. 2015;313(24):2491–2493. doi:10.1001/jama.2015.6613 [8] PHYTOTHERAPY RESEARCH Phytother. Res. 23, 597–602 (2009) Published online 9 October 2008 in Wiley InterScience (www.interscience.wiley.com) DOI: 10.1002/ptr.2625 [9] Romano, L.L. & Hazekamp, Arno. (2013). Cannabis oil: Chemical evaluation of an upcoming cannabis- based medicine. Cannabinoids. 1. 1-11.

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