CBD (cannabidiol) is a compound that is usually extracted from industrial hemp.
Many plants contain cannabinoids, and people often confuse CBD with THC (tetrahydrocannabinol) which is another type of cannabinoid. Unlike THC, CBD does not cause a “high” or euphoric effect because it does not affect the same receptors as THC.
By law, industrial hemp from which CBD is extracted must contain no more than 0.3 percent THC to be considered hemp, otherwise, growers are at risk of prosecution under federal law.
CBD has been credited with relieving anxiety, inflammation, insomnia, and pain, although currently, the most scientific proof rests with its effects in people with epilepsy. Epidiolex is a prescription CBD oil that was FDA approved in June 2018 for two rare and severe forms of epilepsy, Lennox-Gastaut syndrome (LGS) and Dravet syndrome.
Preliminary studies have shown a favorable effect for CBD for reducing pain; however, more research is needed in the form of larger well-designed trials of longer duration to determine its long-term efficacy and safety.
CBD is thought to work by reducing inflammation in the brain and nervous system via an effect on cannabinoid and other receptors, ion channels, anandamide (a substance that regulates our response to pain) and enzymes.
An extensive 2018 review on the use of cannabis and cannabidiol products for pain relief stated:
-Cannabinoids do not seem to be equally effective in the treatment of all pain conditions in humans
-Cannabinoids are not effective against acute pain
-Cannabinoids may only modestly reduce chronic pain
-CBD in combination with THC is recommended by the European Federation of Neurological Societies as a second or third-line treatment for central pain in multiple sclerosis, and by Canadian experts as a third-line agent for neuropathic pain
-22 out of 29 trials investigating cannabis/cannabinoid use for chronic non-cancer pain (neuropathic pain, fibromyalgia, rheumatoid arthritis, and mixed chronic pain) found a significant analgesic effect and several reported improvements in other outcomes like sleep or spasticity
-5 randomized trials showed Cannabis provided >30% reduction in pain scores for people with chronic neuropathic pain (such as that from diabetes, HIV or trauma)
-A Cochrane review found all cannabis-based medicines to be superior to placebo or conventional drugs for neuropathic pain; however, some of these benefits might be outweighed by potential harms such as sedation, confusion, or psychosis. Most products contained THC.
Most studies involved cannabis use or combination CBD/THC products; few studies involved only CBD oil. Many manufacturers of CBD products have based their claims on cannabis studies which have shown a favorable effect; however, it is not apparent whether CBD by itself does have these effects. More trials are needed.