Cannabis was once viewed as a single entity, and researchers – even 100 years ago – were clueless as to why it produces the remarkable therapeutic effects that it does. Fast forward to 2018, and we now know that cannabis has more than 100 compounds, called cannabinoids, which impact one of the body’s most vital systems – the endocannabinoid system (ECS).
The ECS helps to keep our mental and physical health in balance, regulating variables such as pain sensitivity, immune system response and cognition via cannabinoid receptors. Cannabidiol (CBD), an extremely popular non-psychoactive chemical from the plant, appears to play an integral role in this regulation.
The groundswell of interest behind CBD is no shock – cannabis without the high is what many people have been looking for decades, with their only reason for avoiding the plant being the psychoactive stigma. However, it took a long time for researchers to identify what components were causing these intoxicating effects, and whether the plant had significant therapeutic potential. Indeed, the medicinal value of cannabis is now greater than ever since the psychoactive effects can be siphoned off if necessary, as will be explained later in regard to CBD’s ability to treat several mental illnesses.
In addition to treating notorious ailments, CBD may also help people to slash their intake of prescription drugs. Painkillers, like opioids, may be great for soothing pain, but the risk of addiction with sustained use and death by overdose has made these drugs increasingly problematic. Selective serotonin reuptake inhibitor (SSRI) drugs, used to treat depression and anxiety, can also produce worrying side effects, such as drowsiness, nausea, restlessness and impotence.
CBD’s positive effect on the central nervous system
Epilepsy is a disease of the central nervous system. While many forms of the condition are manageable with existing anti-seizure drugs, patients with intractable conditions are not so fortunate. Children affected by conditions like Lennox-Gastaut syndrome are prone to suffering debilitating seizures around the clock, which severely affect their development. However, CBD-dominant cannabis oil is proving to be life-changing for many children and their families.
Epilepsy is extremely complex but can be boiled down to a loss of balance between excitation and inhibition in the brain. In a nutshell, CBD helps to restore this balance, which in turn reduces – and in some cases, eliminates – the seizures. In 2018, the Food & Drug Administration (FDA) in the United States approved Epidiolex, a pure, plant-derived CBD solution.
There is optimism that the regenerative effect CBD has on the hippocampus could be key in treating Alzheimer’s, and perhaps other neurodegenerative diseases. Our long-term memory is stored in the hippocampus, and a connection has been made with Alzheimer’s disease and volume loss in this region of the brain. Much of the leading neuroscientific research on CBD has been carried out in Brazil, and in February 2017, the country’s government permitted CBD oil treatment for a patient with Alzheimer’s. The restorative properties CBD has in the hippocampus could also be useful for treating memory impairment in long-term cannabis users.
CBD – an unlikely remedy for mental illness?
Due to a lack of clinical evidence on CBD and cannabis in general, a result of long-time prohibition, case reports and surveys have played a big role in finding out common reasons for using CBD. Interestingly, many are taking CBD to relieve symptoms of anxiety and depression, and even patients with post-traumatic stress disorder (PTSD) may experience some relief from the compound – however, PTSD sufferers may benefit more from a treatment consisting of THC as well to combat the flashbacks.
Research from 1993 shows that CBD inhibits cortisol secretion, therefore suppressing stress – anxiety is notorious for being amplified by high levels of stress. There are also early indications that CBD can interfere with mechanisms in the opioid system responsible for addiction.
Depression is now a top priority of the World Health Organization – more than 4 percent of the global population are affected by the condition, which has a lack of effective solutions. While some benefit from SSRIs, and the evidence does show these drugs work better than a placebo, there are clear limitations – not least the fact that patients have to take them for two weeks before enjoying an improvement in mood. Studies on humans may be scarce, but research on rodents suggests that CBD can restore the hippocampus and the prefrontal cortex from the initial dose with lasting effects. Results from rodent studies are not always replicated in humans but are often a great guide for future research.
Informing the public about which cannabis products are beneficial for mental illness is critical, as is demonstrated with both psychosis and schizophrenia. These conditions can be triggered by consumption of THC-rich cannabis, because of the cannabinoid’s psychoactive properties. However, CBD is a potent anti-psychotic, as an antagonist of the CB1 receptor. Curiously, CBD’s anti-psychotic properties are much different to those of typical anti-psychotic drugs. But this is a clear example of where some cannabis products could work wonders, while others may make matters worse.
CBD has encouraging potential as a replacement medication for anxiety patients, as confirmed by a handful of studies, both on rodent and in patients with social anxiety. CBD’s anxiolytic effects may come from activating 5-HT1A receptors in the serotonin receptors, rather than benzodiazepine receptors – this is where the anti-panic effects of CBD seem to come from. Most CBD products (except topicals) can help with relieving anxiety, but the rapid onset of effects delivered by CBD vape oil and e-liquid make vaping a preferential treatment, especially for soothing panic attacks and sudden burst of anxiety, such as an unusual social situation or public speaking event.
Can CBD treat physical pain?
Medical cannabis has long been used as an alternative remedy for chronic pain, but there is less research on the benefits of CBD as an isolated treatment. THC helps to reduce the sensation of pain as a partial, albeit potent agonist of the CB1 receptor.
While CBD does not connect with the receptor in this way, it does inhibit the breakdown of the endocannabinoid and CB1 receptor agonist anandamide. There is some debate as to how CBD manages this, but one study indicates that CBD stops anandamide from being degraded by the enzyme fatty acid amide hydrolase (FAAH), by binding with fatty acid-binding proteins (FABPs), which typically transport anandamide molecules to FAAH enzymes.
On this evidence, it is feasible that CBD works as a treatment for chronic pain. Furthermore, anandamide and CBD also interact with another pain-influencing receptor, TRPV-1. Both compounds are agonists of TRPV-1 receptors, which can be activated to dampen pain. It is likely these receptors, in addition to the sparsely-found CB1 receptors in the skin, that are agonised by CBD topicals which are used for pain relief.
CBD – a novel anti-inflammatory
Conditions caused by chronic inflammation are on the rise – some studies suggest that gut problems are the root cause for inflammation throughout the body, in which case CBD edibles would be a suitable treatment. Irritable bowel syndrome (IBS), inflammatory bowel diseases (IBD) such as Crohn’s and ulcerative colitis and arthritis are all inflammatory conditions which may be eased with CBD treatment.
Few drugs have been developed which can effectively regulate immune system response, and this system is notorious for becoming hyperactive and attacking organs and cells in the host, such is the case with the autoimmune disorder rheumatoid arthritis. However, CB2 receptors have been found in the peripheral tissues of the immune system, suggesting that activation may have an immunomodulatory effect.
Sure enough, anandamide has been shown to have a regulatory effect on inflammation, as has another endocannabinoid called 2-Arachidonoylglycerol (2-AG). It is unknown whether CBD inhibits 2-AG breakdown as it does with anandamide but is clear that the cannabinoid has some potency as an anti-inflammatory. Not to mention, side effects with CBD are less of an issue than with non-steroidal anti-inflammatory drugs (NSAIDs), which can cause stomach ulcers, headaches and excessive bleeding.
Until we know more about the ECS and the specific properties of each cannabinoid, cannabis science is like a jigsaw puzzle where we have some idea of the final picture, but which still has several pieces missing. While many cannabis advocates have good intentions, it’s important not to overstate potential benefits where we don’t have clinical evidence, lest patients stop taking their current medication. Future research will also have to focus on what doses of CBD provide the most therapeutic benefit.