CBD, or cannabidiol, is a chemical compound found in the cannabis plant. It is gaining popularity for its potential therapeutic effects. Unlike the main psychoactive compound in cannabis, THC, CBD does not produce a “high” or intoxication. Research shows CBD may benefit people with conditions like chronic pain, anxiety, and epilepsy. But what exactly does CBD do to your brain? Keep reading to learn how CBD interacts with brain receptors and influences neurotransmitters to produce its effects.
How Does CBD Affect the Brain?
CBD interacts with the endocannabinoid system (ECS), a complex cell signaling system in all mammals that helps regulate essential functions like sleep, appetite, memory, mood, and more. The ECS produces its own cannabinoids called endocannabinoids that bind to receptors in the brain and body. CBD can mimic these endocannabinoids and also influence levels of natural cannabinoids like anandamide, indirectly impacting ECS functioning.
The Endocannabinoid System Explained
The endocannabinoid system consists of three core components:
- Endocannabinoids – cannabinoids made by the body like anandamide and 2-AG
- Metabolic enzymes – break down endocannabinoids after they are used
- Cannabinoid receptors – CB1 and CB2 receptors found all over the brain and body
Endocannabinoids bind to cannabinoid receptors to signal between cells and regulate biological processes based on demand. The two main endocannabinoids are anandamide and 2-AG (2-arachidonoylglycerol). They are synthesized on-demand from cell membrane lipids.
After endocannabinoids interact with receptors, enzymes like fatty acid amide hydrolase (FAAH) break them down to terminate signaling. This prevents over-signaling and maintains homeostasis, or internal balance.
CB1 and CB2 Receptors
The two main cannabinoid receptors are CB1 and CB2:
- CB1 receptors – Most abundant in the central nervous system. Found in brain areas involved in cognition, memory, anxiety, pain perception, motor function, and more.
- CB2 receptors – Found primarily in immune cells and peripheral nervous system. Play a role modulating inflammation and pain.
CBD interacts with both CB1 and CB2, but has a higher affinity for CB2. Unlike THC, CBD has low affinity for CB1 and does not directly activate receptors or cause psychoactivity. However, CBD may block or change the shape of CB1, indirectly altering its signaling ability.
Modulating Neurotransmitters
Although CBD does not bind directly to neurotransmitter receptors, it may change levels of neurotransmitters like glutamate, serotonin, and GABA in the brain. Neurotransmitters relay signals between neurons and influence processes like pain, anxiety, addiction, appetite, and sleep.
- Glutamate – CBD affects glutamate levels, an excitatory neurotransmitter linked to brain functions like learning, memory, and anxiety. CBD may protect against glutamate toxicity and reduce glutamate release.
- Serotonin – Impacts mood, social behavior, sleep, digestion, pain, and more. CBD may boost serotonin levels in a dose-dependent manner by acting on serotonin receptors.
- GABA – Primary inhibitory neurotransmitter that regulates anxiety. CBD may increase GABA levels and activate GABA receptors, producing calming effects.
By interacting with endocannabinoid receptors and enzymes, CBD may balance neurotransmitter activity and homeostasis. But more research is still needed on the exact mechanisms.
CBD Effects on Brain Health and Function
Research indicates CBD may benefit certain brain conditions and influence brain function in various ways. However, large human studies are still limited.
Epilepsy
In 2018, the FDA approved CBD oral solution Epidiolex for treating Lennox-Gastaut syndrome and Dravet syndrome, two rare and severe forms of epilepsy. CBD is thought to reduce seizure frequency by suppressing glutamate activity, boosting GABA, and modulating calcium channels.
In studies of Epidiolex, nearly 40% of patients saw at least a 50% reduction in seizures. CBD also showed improvements in sleep and anxiety in child epilepsy patients. However, adverse effects included diarrhea, vomiting, fatigue, and abnormal liver tests. More research is still needed on the long-term efficacy and safety of CBD for epilepsy.
Chronic Pain
CBD may alleviate chronic pain by reducing inflammation, interacting with endocannabinoid receptors, and altering neurotransmitter activity. Human studies found CBD effectively reduced chronic pain and improved sleep and mobility in conditions like arthritis, multiple sclerosis, neuropathy, and cancer. Topical CBD also helped reduce inflammation and pain in arthritis patients.
While promising, more clinical trials on larger patient samples are still needed. CBD may complement pain medications by allowing lower doses with fewer side effects, but should not be used as a complete replacement without medical guidance.
Anxiety and Depression
Research on CBD for anxiety and depression has shown mixed results. Smaller studies have found CBD may reduce anxiety behaviors in disorders like OCD, PTSD, social anxiety, and panic disorder. One study found CBD comparable to the antidepressant imipramine for treating depression.
However, two larger meta-analyses found insufficient evidence to draw conclusions on the efficacy of CBD for anxiety and depression. More high-quality, placebo-controlled human trials are needed.
Addiction
Early research indicates CBD may help reduce cravings and anxiety in substance use disorders. A 2021 randomized trial found CBD combined with psychosocial care was superior to a placebo for abstaining from cannabis use.
Animal studies also found CBD reduced morphine, heroin, and cocaine-seeking behaviors. However, human research is still extremely limited. More randomized placebo-controlled trials are necessary to confirm CBD’s potential for addiction treatment.
Neurodegenerative Diseases
While findings are preliminary, CBD is being studied for neuroprotective properties that could benefit neurodegenerative diseases like Alzheimer’s and Parkinson’s.
In animal models, CBD prevented cognitive impairment and loss of neuronal function in Alzheimer’s disease. It may work by reducing inflammation, oxidative stress, and amyloid beta toxicity. CBD also showed neuroprotective effects in Parkinson’s models by preventing neuron damage and stimulating neuroplasticity.
However, current human research is extremely limited. No conclusions can be made yet on CBD’s efficacy for slowing neurodegeneration in humans. More clinical trials are underway.
Psychosis and Schizophrenia
Contrary to popular belief, high doses of oral CBD do NOT appear to help treat psychosis or schizophrenia symptoms. In fact, CBD may actually worsen symptoms like paranoia.
In clinical trials of CBD for schizophrenia and psychosis, CBD had no significant benefits versus a placebo. However, it did come with side effects like diarrhea, fatigue, and liver abnormalities.
More research is still needed, but CBD should be avoided in schizophrenia patients until more is known about safe dosing and potential interactions with antipsychotic medications.
Cognitive Function
Small studies suggest CBD may temporarily improve symptoms of social anxiety, behavioral issues, and impulsivity in patients with conditions like ADHD and autism. However, there is insufficient evidence that CBD enhances cognition or memory in healthy individuals.
Despite marketing claims, CBD is NOT scientifically proven to boost focus, concentration, or memory recall in normal healthy users. In fact, high doses may even impair cognition. More research is needed to understand CBD’s effects on cognitive function.
Is CBD Psychoactive?
Despite common misconceptions, CBD is NOT psychoactive and does not cause intoxication or a “high” by itself. However, some CBD products do contain variable traces of THC, the main psychoactive compound in cannabis.
Full-spectrum CBD extracts contain a full profile of plant cannabinoids, including up to 0.3% THC. Broad spectrum CBD has a wide cannabinoid profile but with THC removed. CBD isolate is pure CBD only, with no other cannabinoids or THC.
Consuming full-spectrum CBD may lead to failed drug tests or slight intoxication in sensitive users when taken in very high doses over 600mg per day. Those wanting to avoid THC should use broad spectrum or isolate products.
Drug Testing
Most standard workplace drug screens test for THC only, not CBD or other cannabinoids. However, full-spectrum CBD products may still contain enough THC to produce a positive result.
Studies found that a single dose of up to 1,500mg CBD isolate is unlikely to cause a positive drug test. But chronic full-spectrum CBD use or very high single doses may put someone at risk of a failed screening.
Those subject to drug testing should use CBD isolates or broad spectrum oil with undetectable levels of THC. Testing cleansers may also minimize THC residue prior to a screening.
Legal Status
Under the 2018 Farm Bill, CBD derived from industrial hemp containing less than 0.3% THC is legal at the federal level. However, some state laws still prohibit CBD sales. Check your local laws before purchasing CBD products.
It is illegal to market CBD by adding it to food or labeling it as a dietary supplement. The FDA currently prohibits CBD in food, beverages, dietary supplements, and pet food because it has an active drug approval for epilepsy.
Despite federal legality, transporting CBD across state lines or boarding flights with CBD may still carry legal risks. TSA officers allow CBD products in carry-on bags, but state laws at your destination should be checked prior to travel.
Side Effects and Safety Concerns
CBD is generally well tolerated and considered safe at typical doses used orally or topically. However, potential side effects can occur.
Common Minor Side Effects
- Diarrhea
- Appetite changes
- Fatigue
- Weight changes
- Nausea
These mild side effects often improve with continued use or dose adjustment. Using CBD with food may also help minimize gastrointestinal issues.
Drug Interactions
- Blood thinners – CBD may increase bleeding risk
- Benzodiazepines like Xanax or Ativan – CBD may increase sedation
- Immunosuppressants – May increase immunosuppressant levels in the blood
- Heart medications – CBD may lower blood pressure
- Anticonvulsants – CBD could affect metabolism
- Chemotherapy – May interact with cancer treatments
Consult your doctor before using CBD if you take any medications or supplements. Never alter medication doses without medical oversight.
High Doses and Chronic Use
Very high CBD doses over 1500mg daily may worsen cognitive deficits, thyroid problems, gastrointestinal issues, and liver toxicity potential. Chronic, long-term use also requires monitoring for side effects.
Consult a doctor experienced in cannabis or functional medicine for guidance on safe CBD dosing and avoiding potential drug interactions or adverse effects with chronic use.
Liver Injury
High doses of CBD have been linked, in some cases, to elevated liver enzymes or clinically significant liver changes. Consult your doctor if you have liver problems before taking CBD. Use the lowest effective dose and have labwork monitored with long-term use or high CBD dosage.
Fetal Development
Very little research exists on CBD safety during pregnancy and breastfeeding. Potential risks are unclear, so CBD should be avoided during pregnancy unless a doctor recommends it.
Choosing a Safe, High Quality CBD Product
With an unregulated CBD market, it is important to choose products carefully and look for the following signs of quality:
- Organically grown USA hemp
- Extracted with supercritical CO2, not solvents
- Contains 0% THC to avoid drug testing risks
- Third-party lab tested for purity and potency
- GMP certified manufacturing facility
Only purchase CBD from reputable brands that provide recent third-party lab reports for every batch. Read the label carefully to confirm the CBD content, type of extract, and ingredients.
Consult a knowledgeable practitioner for guidance on choosing high quality CBD products that fit your needs.
Key Takeaways on CBD and the Brain
- CBD interacts with endocannabinoid receptors and enzymes to mediate neurotransmitter activity and maintain homeostasis.
- Research indicates potential therapeutic benefits for conditions like chronic pain, anxiety, addiction, and epilepsy.
- However, human research is still limited and more placebo-controlled trials are needed.
- CBD is not a cure-all and should NOT replace proven medical treatments without doctor supervision.
- Mild side effects like diarrhea and fatigue are possible. Consult a doctor before using CBD if you have any medical conditions.
- Avoid CBD products with THC to minimize risks with drug testing or sensitivity.
- Work with a knowledgeable practitioner to find a high quality, reputable CBD manufacturer.
While CBD research is ongoing, initial studies indicate a favorable safety profile for many adults. However, each person may respond differently. Work closely with your healthcare provider to determine if CBD is right for your needs and to find the most appropriate dose and product.
Frequently Asked Questions
Does CBD cross the blood-brain barrier?
Yes, CBD can cross the blood-brain barrier to directly interact with receptors and enzymes in the brain and central nervous system. However, it has low bioavailability and only a fraction of the dose makes it to the brain.
Can CBD help with memory?
There is currently no scientific evidence that CBD can improve memory in healthy individuals. Very high doses may even impair cognitive function. However, CBD shows potential for slowing age-related memory loss in animal models. More research is needed.
Is CBD addictive?
No, CBD does not appear to be addictive or have abuse potential, according to World Health Organization research. And a 2021 study found CBD may actually help reduce drug cravings and withdrawal.
Can you overdose on CBD?
It is very difficult to fatally overdose on CBD alone. However, extremely high doses over 3000mg per day may increase side effects or drug interaction risks. Stick to the lowest effective dose under medical guidance.
Does CBD help PTSD?
A few small studies found CBD may help with PTSD-related anxiety and sleep issues. However, evidence is currently insufficient to confirm CBD’s efficacy for PTSD, and more research is necessary.
| Product | Price | Potency | Flavor |
|---|---|---|---|
| CBD oil tincture | $35-125 per bottle | 250-5000mg per bottle | Unflavored or flavored options like citrus, mint, or berry flavors |
| CBD gummies | $30-100 per bottle | 10-50mg per gummy | Many fruity flavor options |
| CBD capsules | $35-90 per bottle | 15-50mg per capsule | Unflavored |
| CBD topicals | $20-200 per product | 2-8% CBD concentration | Unscented or essential oil scented |