Effects of CBD on the Brain and Neurotransmitters Like Serotonin

CBD is a cannabinoid compound found in the cannabis plant. While there are hundreds of unique cannabinoids produced by the plant, CBD in particular has grown in popularity and drawn clinical attention for its therapeutic powers. This is because it is safe and non-psychoactive yet yields several key benefits for the brain and mental health. It’s already being concentrated and employed in medications such as Epidiolex to help treat neurological conditions such as epilepsy. But its applications even span into mitigating anxiety, depression, neurodegenerative conditions and chronic stress. It acts on cannabinoid and other brain receptors to provide these benefits. Through a number of neurological pathways it helps in the regulation of neurotransmitters such as serotonin, GABA, glycine and adenosine directly. It also has indirect effects on vanilloid or pain receptors, in addition to the opioid receptors. Unlocking the secrets of these mechanisms is now a major focus of research. Let’s take a look at the science behind CBD and its interactions with the brain.

Understanding CBD: An Overview

CBD is classified as a cannabinoid. These are naturally created chemicals that cannabis produces from its trichomes, found in the leaves and buds of the plant. Cannabinoids are bioactive and interact with the body’s endocannabinoid system, which plays a crucial role in maintaining internal regulation of enzymes, hormones and nerve signalling. It helps control sleep, mood, appetite, pain, immune function and more. 

Unlike its cousin cannabinoid THC (tetrahydrocannabinol), CBD does not possess psychoactive properties, meaning it does not cause intoxication. This distinction has made CBD an attractive option for those seeking the potential therapeutic benefits of cannabis without the mind-altering effects. As it doesn’t get you ‘high’ or intoxicate, people can use it in their day to day lives without worrying about mental harm or issues like being unable to drive. The legal status of CBD varies across countries. In Australia, it has been legal since 2021 after laws were changed to reschedule it.  

CBD has been found to have anti-inflammatory, analgesic, and anti-anxiety properties. It has been clinically demonstrated to alleviate symptoms of various conditions such as chronic pain, epilepsy, and anxiety disorders. Plus it even displays anti-depressant qualities which are somewhat similar to SSRIs. One of the reasons why CBD has gained so much attention is its interactions with the brain. It has been found to modulate the activity of neurotransmitters, such as serotonin, GABA and glycine. These play a crucial role in regulating mood, sleep, and appetite. By influencing these neurotransmitters, CBD may have a positive impact on mental health and support calmness plus improved mood. In addition, it has neuroprotective capacities, meaning it may help protect the brain from damage and degeneration. This has led to more research into its potential in treating neurodegenerative diseases such as Alzheimer’s and Parkinson’s.

CBD and the Brain

CBD acts on the the brain via the endocannabinoid system (ECS), in addition to working directly with certain brain receptors. The ECS is a network of microscopic receptors located throughout the body, brain and nervous system. When activated by cannabinoids these receptors help other bodily systems signal through lipids molecules. It is also being shown to have neurotransmitter influencing effects. CBD interacts with the ECS by binding to receptors known as CB1 and CB2 receptors. CB1 receptors are primarily located in the brain and are responsible for the cannabinoid’s mental health benefits.

What Neurotransmitters Does CBD Affect?

CBD can influence the production and signalling of a range of neurotransmitters in the brain, either directly by binding with their receptor sites, indirectly through endocannabinoid activity or via neurological pathways such as specific neuronal calcium channels. The primary neurotransmitters CBD acts on include:

  • Serotonin (5-hydroxytryptamine) via the 5-HT serotonin receptors
  • GABA (Gamma-aminobutyric acid) via the GABAa and GABAb receptors
  • Calcium cation signalling via the Vanilloid or TRPV1 pain receptors

Additionally, CBD may affect glycine and adenosine which play a role in central nervous system function.

CB1 Receptor Activity 

When CBD binds to CB1 receptors in the brain, it causes endocannabinoids to be locally produced in the brain like 2-AG and anandamide. Endocannabinoids are chemical messengers that help to facilitate communication between neurons. By stimulating their release, CBD can influence various cognitive functions such as memory, learning, and mood regulation.

Additionally, CBD has been found to have neuroprotective properties, meaning it can help protect the brain from damage and degeneration. Studies have shown that CBD can reduce inflammation and oxidative stress in the brain’s neurons. This effect is beneficial for neurodegenerative diseases such as Alzheimer’s and Parkinson’s which are exacerbated and accelerated by neuroinflammation in the brain.

Does CBD interact with GABA?

In the brain, GABA or Gamma-aminobutyric acid is classified as an inhibitory neurotransmitter. The purpose of it is to slow or block the signalling of certain nerve cells and brain pathways, helping others signal in turn. Effectively it’s a messenger molecule, that helps the brain to avoid muscle spasms, high blood pressure and poor mood. Some cannabinoids including CBD can bind to GABA receptors, promoting reduced feelings of anxiousness and better mood. Terpenes from cannabis are also known to stimulate similar effects. While not as potent as antidepressants such as benzodiazepine or Prozac, the ability of cannabinoids to influence GABA means they can assist in preventing mood disorders and depression symptoms. 

GABA interactions are also how CBD suppresses epilepsy from occurring and reduces the severity of seizures. Normalising GABA activity is key to its anti-epileptic effects. These effects are so powerful that the cannabinoid has now been purified, concentrated and deployed into anti-seizure drugs such as Epidiolex. CBD acts as an anticonvulsant and has been shown in studies to lower both the frequency and severity of seizures. Promoting GABA production leads to better inhibitory regulation in the neurons and lowers hyperexcitability in neurons, leading to a decrease in seizure activity.

How does CBD work with serotonin?

Serotonin is the neurotransmitter in the brain that regulates areas such as memory, learning, mood and cognitive pathways. Ensuring its levels are normalised and stable is key to maintaining a positive and stable mood plus mental state. When consumed, CBD can increase serotonin. It doesn’t do this by acting on the serotonin receptors directly. Rather CBD helps to prevent tryptophan from degrading in the brain. This is an amino acid which the body uses to produce serotonin by synthesising it in the gut. More than 90% of serotonin is created by the intestine, where it then is transported to the brain for neurological functions. By modulating tryptophan, CBD supports greater serotonin production and regulation. It can correspondingly assist with many areas such as mood, depression, anxiety and appetite.

CBD and Vanilloid Receptors

Pain is primarily experienced through nerve signalling from the body to the brain. But the primary receptors responsible for its perception in the mind are called the vanilloid receptors or TRPV1. In particular, they play a key role in nociception or how we feel and experience certain pain types. CBD is being shown in research to stimulate TRPV1 inhibition through the action of certain calcium signalling chemicals such as adenylyl cyclase. The Journal of Pain Research conducted a study into this effect, showing CBD has properties that prevent acute and chronic pain types through modulating the cAMP pathway. It reduces the sensitivity of these pain receptors, helping prevent much of the nerve cell signalling from occurring.

Neurogenesis Potential

Another interesting aspect of CBD’s interaction with the brain is its potential in promoting neurogenesis. Studies are showing it can assist in the growth and development of new neurons. This process is crucial for brain repair and recovery after injury or disease. By stimulating neurogenesis, CBD may contribute to the restoration of brain function and cognitive abilities. For example, a study conducted by the University College London showed even a single dose of CBD could stimulate improved blood flow in the hippocampus and brain regions responsible for learning and memory. They concluded these effects aided neuron development and function, with potential benefits for PTSD, anxiety and Alzheimer’s. 

Benefits of CBD for Brain Health

One benefit of CBD on brain health is its ability to alleviate symptoms of anxiety. Anxiety disorders affect millions of people in Australia. They’re one of the most common mental health disorders. Conventional treatments using antidepressants or medications like Xanax may have unwanted side effects. Many of these compounds like Xanax are also highly addictive and can’t be used for long periods. CBD may help reduce anxiety by interacting with serotonin receptors in the brain, promoting a sense of calmness and relaxation without the intoxicating effects associated with THC. In contrast to many traditional synthetic anxiety medications it is also non-addictive and has much lower side effect risks.

Sleep Quality

CBD has been found to have a positive impact on sleep quality, which is crucial for overall brain health. This occurs through the endocannabinoid system’s ability to help regulate circadian rhythm and the sleep-wake cycle. Sleep deprivation can lead to cognitive impairments, mood disorders, and an increased risk of neurodegenerative diseases. Studies have shown that CBD may improve sleep by reducing anxiety and promoting a deeper, more restful sleep cycle. It can support greater REM sleep length which is the most restorative stage of the sleep cycle where memory formation occurs and neurons are repaired. Over time these properties enable it to enhance cognitive performance, mood and mental energy through better sleep patterns.


Another area of interest is the potential role of CBD in neurodegenerative diseases such as Alzheimer’s and Parkinson’s. While the research is still preliminary, some studies have shown that CBD may possess neuroprotective properties and help reduce inflammation and oxidative stress in the brain, which are key factors contributing to the progression of these diseases. Furthermore, CBD has been found to have antioxidant and anti-inflammatory effects, even for the brain’s neurons. It is neuroprotective and aids in preventing neuron degradation which occurs with many neurodegenerative diseases like Alzheimer’s. In effect, it helps build brain resilience and prevention of excessive excitatory activity which can cause neurotoxicity. These properties also make it ideal in helping with mental performance, focus and reducing the impact of cognitive disorders like ADHD

Studies on CBD and Brain Health

Recently, studies have been conducted to explore the effects of CBD on brain health. For example, a study published in the Journal of Experimental Medicine found that CBD reduced neuroinflammation and improved memory in a rodent model of Alzheimer’s disease. The study commented on the cannabinoid’s capacity to prevent neuro-degradation, plus stimulate reductions in neuroinflammatory and oxidative responses. It was found that CBD wasn’t able to halt the progression of the disease but offered a means of managing symptoms and helping to support a life quality.

One recent study published in the Brazilian Journal of Psychiatry examined the effects of CBD on patients with Parkinson’s disease. The results showed that CBD improved quality of life and reduced comorbidities experienced by many with Parkinson’s such as anxiety and neuroinflammation. This suggests it plays a potential role for CBD in managing Parkinson’s symptoms of conditions associated with Parkinson’s’ and supports better quality of life for those it affects.

In another study published in the journal Journal of Clinical Pharmacology, researchers investigated the neuroprotective properties of CBD in vivo animal models. They noted the cannabinoid’s powerful anti-inflammatory and antioxidative capacities which assisted with neuronal health. Interestingly it was able to reduce signs of oxidative stress in the brain, help in lowering inflammatory cytokines, improve calcium signalling across the brain’s membranes plus control microglial toxicity even at low doses. Each of these inferred positive results on mental clarity, brain fog and cognitive capacity. The findings indicated that CBD helped in preventing brain damage or neurotoxicity, plus improved functional recovery following strokes. 

As CBD continues to gain recognition and acceptance, we can expect to see an increase in research efforts to uncover its full potential for the brain. Future studies may focus on elucidating the optimal doses, identifying specific mechanisms of action, and exploring the potential synergistic effects of CBD with other cannabinoids or compounds like terpenes, antidepressants or SSRIs and nootropics.

Side Effects and Risks of CBD

CBD is considered safe, but it is important to be aware of potential side effects. While rare, some individuals may experience dry mouth, nausea, fatigue, or changes in appetite. These side effects are typically mild and temporary. The effects of CBD and success rates in using it can vary depending on the individual and the dosage. Factors such as body weight, metabolism, and the method of consumption can all play a role in how CBD affects each person. It is always recommended to start with a low dosage and gradually increase it if necessary, under the guidance of your doctor.

Aside from the short-term effects mentioned earlier, there is ongoing research to determine the long-term effects of CBD. Due to the limited research available in this area, it is essential to approach CBD use with caution, especially if you have existing medical conditions or are taking other medications. CBD in combination with some medications can cause liver complications so this must be particularly noted. It can inhibit the activity of enzymes in the liver that are responsible for metabolizing drugs. This means that CBD has the potential to alter the way certain medications are processed in the body, potentially leading to unwanted side effects or reduced efficacy of the medication.

While CBD is derived from the cannabis plant, it does not produce the psychoactive effects commonly associated with marijuana use. CBD products in Australia are required to contain less than 0.3% THC (the psychoactive compound in cannabis) to be legally sold. However, it is important to note that some CBD products may still contain trace amounts of THC, which could potentially show up on a drug test. Another aspect to consider is the quality and purity of CBD products. The CBD industry in Australia is still largely unregulated, which means that not all products on the market may meet standards of quality and safety. It is crucial to research and choose reputable brands that provide third-party lab testing to ensure the product’s potency and purity.


CBD’s effects on the brain are both exciting and astounding in their breadth of benefits plus mechanisms of action. It can help in the regulation of many neurotransmitters including serotonin, GABA, glycine and adenosine. Plus the cannabinoid assists in reducing pain by modulating vanilloid receptor activity. While more studies are needed to fully understand its benefits and risks, CBD has shown promise in promoting brain health and may offer new avenues for therapeutic interventions in the future. Some of these applications include helping reduce anxiety and depression, assisting with neurodegenerative diseases like Alzheimer’s, preventing epileptic seizures, plus aiding with sleep, cognition and neuron health.