How Does CBD Work?

How Does CBD Work?

CBD is famous for treating rare forms of childhood epilepsy and multiple sclerosis (For example, the CBD drug, Epidiolex (GW Pharmaceuticals, Salisbury, UK), has been approved to treat patients from the age of two years old with Dravet Syndrome and Lennox-Gastaut Syndrome. In addition, Sativex (GW Pharmaceuticals, Salisbury, UK) which is derived from Cannabis cultivars containing both THC and CBD, has been approved for use in the UK and is used to treat pain symptoms associated with multiple sclerosis).

However, one of the most remarkable things about CBD is its sheer number of potential therapeutic applications. For example, there is evidence, mainly derived from animal studies and in vitro experiments, to suggest that CBD may have analgesic (pain-relieving), anti-inflammatory and neuroprotective properties, and potential therapeutic value in the treatment of disorders such as anxiety, addiction and depression, which in turn can help to relieve symptoms associated with menopause, amongst other ailments.

But What Exactly is the Biological Basis for this Wide Range of Potential Medical Uses?

Scientists are still studying the mechanisms involved but they believe that a key part of the answer lies in CBD’s ability to influence a wide range of receptor systems in the brain and body.

The brain contains large numbers of highly specialised cells called neurons. Each neuron connects to many others through structures called synapses. These are sites where one neuron communicates to another by releasing chemical messengers known as neurotransmitters.

A neuron’s sensitivity to a specific neurotransmitter depends on whether or not it contains a receptor that “fits” that transmitter.

Brain receptors are not only sensitive to neurotransmitters produced naturally within the brain, like dopamine or serotonin, but also chemical messengers produced outside the body, such as plant cannabinoids like THC or CBD. Once these plant-derived compounds arrive in the brain, they can influence brain activity by interacting with receptors on neurons.

Whilst THC binds directly to cannabinoid receptors in the brain (which partly explains why THC is intoxicating, in contrast to CBD), CBD is believed to interact with the CB1 and CB2 receptors by inhibiting the enzymes that break down the body’s own naturally-produced cannabinoids (known as Endocannabinoids).

CBD also influences many non-cannabinoid receptor systems in the brain, by interacting with receptors sensitive to a variety of drugs and neurotransmitters. These include opioid receptors, known for their role in pain regulation. Opioid receptors are the key targets of pharmaceutical pain killers and drugs of abuse such as morphine, heroin, and fentanyl. CBD can also interact with dopamine receptors, which play a crucial role in regulating many aspects of behaviour and cognition, including motivation and reward-seeking behaviour.

This raises the possibility that CBD’s ability to influence either opioid or dopamine receptors may underlie its ability to reduce drug cravings and withdrawal symptoms, effects directly relevant to the treatment of addiction. However, more research on CBD’s interactions with the opioid and dopamine receptor systems is still needed.

CBD’s therapeutic potential with respect to addiction also extends to the serotonin system. Animal studies have demonstrated that CBD directly activates multiple serotonin receptors in the brain. These interactions have been implicated in its ability to reduce drug-seeking behaviour. CBD’s influence on the serotonin system may also account in part for its anti-anxiety properties, which have been robustly demonstrated across both human and animal studies.