It seems like everywhere I turn these days a CBD tincture, shampoo, muscle cream or oil is being sold. They’re in mall kiosks, barbershops, local convenience stores, even in gas stations. To further complicate things, it’s estimated that several hundred CBD companies exist manufacturing a seemingly overwhelming number of products.
It’s also important to note that since these products are viewed as “supplements” they are not closely regulated by the FDA in terms of their safety and purity. Consequently, preparations differ drastically from company to company and ingredients listed on their labels aren’t always accurate. Legality issues also exist, with most states approving the use of marijuana or marijuana-derived products for medicinal purposes, however, it remains illegal on a federal level.
With all the hype about CBD, it’s important that we take a step back and evaluate the available evidence on the topic to better understand the potential risks and benefits of this treatment modality.
How Does CBD Work?
A variety of different cell types in our body contain cannabinoid receptors which are part of the endocannabinoid system. Although there is still much to learn about how this system works, as its discovery occurred fairly recently in the 1990s, from an evolutionary standpoint it must be advantageous or it would have been selected out by nature.
There are two types of CBD receptors, CB1 and CB2. CB1 receptors are heavily concentrated in the brain. When activated, it results in changes in mood, emotions, appetite and pain perception.  CB2 receptors are found on immune cells, hematopoietic stem cells, or those cells responsible for making blood cells in our body, and along peripheral nerve endings. CB2 receptors are believed to play a role in modulating pain and are responsible for the anti-inflammatory effects of CBD.
Interestingly, our bodies make their own cannabinoids, called endocannabinoids, specifically Anandamide and 2AG which are believed to have a calming, pleasurable effect. This is likely why Anandamide and 2AG are present in a mother’s breast milk–to have a soothing effect on the baby. 
Does CBD Make you High?
Cannabidiol, or CBD, is a phytocannabinoid and one of approximately 80 active chemicals found in medical and recreational cannabis. [1,2] Another commonly known cannabinoid is tetrahydrocannabinol, or THC, which is responsible for the psychoactive effects of cannabis–essential giving users a sensation of being “high.”
Pure CBD will not cause psychoactive effects and is referred to as “broad-spectrum.” However, not all products are broad-spectrum. Many preparations are “full-spectrum” which allows for up to 0.03% THC to be present. If you wish to avoid possible psychoactive effects, it is best to avoid preparations that are full-spectrum.
What are the Potential Benefits?
The available evidence suggests that CBD could have the following therapeutic benefits:
Anti-inflammatory, pain-relieving effects: CBD is believed to have anti-inflammatory and pain-relieving effects. As such, it is now being used to treat neuroinflammatory diseases like, Multiple Sclerosis which can be quite painful.  Studies have shown improvement in pain and spasticity in patients suffering from Multiple Sclerosis when using formulations containing both CBD and THC.  Animal studies have also shown CBD to be beneficial in terms of reducing pain related to osteoarthritis, however, this has yet to be proven in large scale, randomized, controlled trials in human beings. 
Combat seizure and epilepsy: A CBD oral solution has been approved by the FDA for the treatment of two rare, but severe, forms of epilepsy. In a number of studies, it was shown to reduce seizures or stop them altogether. [2,3,4]
Reduce nausea: Animal studies suggest that CBD can help reduce nausea.  Preclinical research suggests that CBD preparations may also be beneficial for reducing chemotherapy-related nausea, however, this has yet to be substantiated in randomized, controlled, human trials. 
Help with psychosis: It is believed to have anti-psychotic features and may play a role in the treatment of Schizophrenia in the future. 
Reduce anxiety: CBD is also believed to have anti-anxiety effects.  In a double-blinded, placebo-controlled trial, patients who were administered 400mg of CBD saw a substantial reduction in their level of social anxiety by targeting the limbic system and paralimbic areas of the brain. 
What are the Risks?
Although research is lacking in long-term safety data, from the data available, CBD appears to be fairly safe and well-tolerated at a wide range of doses. Some common side effects include fatigue, diarrhea, and changes in appetite. There are also potential drug-drug interactions, especially when consuming a blood thinner like Warfarin, thyroid medications, or other medications processed by CP450. It may also be unsafe for those with liver disease and pregnant/breast feeding women.
For brevity's sake, we will review different CBD products in a future post. In the meantime, it is always recommended that a patient speaks with their doctor first before starting a course of CBD and for specific recommendations on dosage and formulations.
How about you? What has your experience been with CBD?
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