Cannabidiol (CBD) oil and other CBD products have become increasingly popular with consumers looking for an alternative treatment for a range of ailments, conditions, and diseases.
Cannabis plants contain a group of substances called cannabinoids. Although there are more than 100 cannabinoids, the two most studied cannabinoids are tetrahydrocannabinol (THC) and CBD.
THC is a psychoactive compound that is responsible for most of the psychological effects and the high that people often associate with marijuana. CBD is not psychoactive in the same way.
While THC does have psychoactive effects, it does not lead to high or euphoric feelings, and other such effects associated with recreational cannabis smoking.
Learn more about what it feels like to be high here.
Researchers are studying CBD as a treatment for a wide range of conditions, but research supporting its benefits is limited.
Currently, the Food and Drug Administration (FDA) has only approved one drug that contains CBD. The FDA also state that it is illegal to sell CBD as a dietary supplement or food additive.
Keep reading to learn more about some of the potential effects of CBD oil that researchers are investigating, as well as the risks and side effects.
In 2018, the FDA approved Epidiolex as the first pharmaceutical-grade CBD medication.
Epidiolex treats seizures in two rare and severe epilepsy types called Lennox-Gastaut syndrome and Dravet syndrome in people age 2 years and older.
Clinical trials found that when people with Lennox-Gastaut and Dravet syndromes take Epidiolex with other seizure medications, they have fewer seizures than people taking a placebo with other seizure medications.
There is not enough research to confirm whether CBD would help people with other, more common forms of epilepsy.
People around the world have used cannabis for medicinal purposes, including pain relief, since around 2900 B.C.
Researchers have suggested that cannabinoids may be responsible for the pain-relieving effects associated with cannabis. However, few studies have currently tested how CBD independently affects pain.
A 2018 review examined 47 studies, including 4,743 people, of using cannabis and cannabinoids for chronic pain other than cancer pain. The review found moderate evidence that cannabinoids reduce pain when compared with placebo groups.
Adverse side effects were more common in people taking cannabinoids than placebo.
A review of observational studies in the Journal of Central Nervous System Disease research supports the use of nabiximols (Sativex), an oral spray containing THC and CBD, combined with other therapies for multiple sclerosis-related pain. Some countries have approved Sativex, but the FDA has not yet approved Sativex for use in the U.S.
The National Center for Complementary and Integrative Health (NCCIH) is funding new research into cannabinoids and their potential in pain management.
Studies also show that pain from peripheral neuropathy may also ease with CBD use.
New clinical trials are also in the pipeline to individually test CBD for chronic pain, particularly neuropathic pain.
The relationship between cannabis and anxiety can be inconsistent. An article in Neuropsychopharmacology notes that some users of cannabis report that the main reason that they use it is to reduce anxiety. However, others report panic and anxiety as side effects.
These conflicting results may be because low doses of THC in cannabis are linked with reducing anxiety, while high doses seem to cause anxiety.
The article in Neuropsychopharmacology also indicates that CBD decreases the anxiety-causing effects of THC. In animal studies, CBD also appears to inhibit anxiety in a similar way to other anti-anxiety drugs.
The study of 24 people with generalized social anxiety disorder found that those who took 600 mg of CBD before a simulated public speaking test had less anxiety than those who took a placebo.
Although the results of this study were promising, researchers need to conduct more studies involving more people to see if they yield similar results.
Learn more about CBD oil and anxiety here.
Cancer treatments, such as chemotherapy, can cause nausea and vomiting. Doctors often treat chemotherapy-induced nausea and vomiting (CINV) with a medicine called an antiemetic.
One earlier study found that compared to placebo, adding a combination of THC and CBD to conventional antiemetic treatment provided better protection against delayed CINV.
A 2018 study in rats observed that treatment with CBD prevented a surge in serotonin levels in the rats’ interoceptive insular cortex (IIC) following an injection of a nauseating chemical compound.
In humans, the IIC is the region of the brain that is responsible for nausea. These findings indicate that scientists could potentially develop CBD into antinausea treatments for people having chemotherapy.
According to a 2019 article in Future Oncology, cannabinoids may also prevent other side effects of chemotherapy, including pain, loss of appetite, and organ toxicity.
Studies examining CBD as an antinausea treatment are relatively new, and scientists need to carry out more research before they can confirm whether CBD prevents chemotherapy side effects.
Substance use disorder affects a person’s brain and behavior and may make them unable to control their use of legal or illegal medication or drugs.
According to a 2015 systematic review, CBD may influence some of the brain circuits involved in addiction and drug-seeking behaviors and regulate stress response and compulsive behaviors.
The review of animal and human studies showed that CBD might help with addiction to opioids and psychostimulants and could benefit cannabis and tobacco dependence.
In 2018, researchers conducted a study in rats to see whether CBD prevented relapse to drug use.
The researchers discovered that CBD reduced relapse provoked by drug and stress cues and decreased anxiety and impulsivity. Furthermore, relapse remained reduced 5 months after the experiment.
A 2019 double-blind randomized placebo-controlled trial indicates that CBD may be helpful for people with heroin use disorder.
In drug-abstinent people with heroin use disorder, CBD reduced the anxiety and craving induced by drug cues compared to placebo. CBD also decreased physiological measures, such as heart rate and salivary cortisol levels. The researchers also observed these effects a week later, which may suggest that the results are long-lasting.
Researchers need to conduct follow-up studies to investigate the use of CBD for substance use disorder.
Studies have shown that alongside psychiatric treatment, CBD can reduce symptoms of post-traumatic stress disorder.
One recent study, in particular, found that participants saw a reduction in trouble sleeping and nightmares. All participants continued to use CBD throughout the study and experienced no side effects.
That said, researchers noted that many more studies must take place before there is conclusive evidence.
A 2018 review notes that some studies indicate antidepressant activity after CBD intake in animal models.
Researchers state that CBD exhibits a clear anti-stress effect after short- or long-term use, and in some tests, CBD acted as an antidepressant.
That said, human testing must take place before researchers make any definitive conclusions.
The FDA has only approved one CBD product, Epidiolex, for two rare forms of epilepsy, and there is still limited evidence about how CBD affects the body.
During the review and approval process for Epidiolex, using CBD was found to have potential risks and side effects, such as:
- causing liver injury
- interacting with other medications, which may cause severe side effects
- increasing the risk of sedation and drowsiness when taken with alcohol or medicines to treat anxiety, stress, panic, or sleep disorders
- changing alertness
- decreasing appetite
- causing diarrhea
Also, many aspects of using CBD remain unanswered, such as:
- What happens with the sustained use of CBD?
- What dosage of CBD triggers known risks?
- Does the method of consumption affect intake (orally, smoking, vaping, or topical)?
- Does CBD affect the developing brain?
- How does CBD affect the developing fetus and breastfed babies?
- Does CBD affect male fertility, as some studies in animals have indicated?
CBD products are widely available and marketed as drugs, dietary supplements, food, cosmetics, and health products for animals.
Unlike FDA-approved drug products, any unapproved products have not been subjected to FDA evaluation to determine whether they are effective at treating the condition they claim to treat. Also, the FDA would not have assessed the products for proper dosage or side effects and safety concerns.
False claims may lead people not to take their conventional medicine or put off getting medical care from a healthcare professional. A person should always discuss the best way to treat diseases or conditions with their doctor.
People may also raise questions about the quality of some CBD products. Some unapproved products that the FDA tested did not contain the CBD levels that the manufacturers claimed. Others may contain unsafe contaminants.
Doctors and healthcare providers also recommend only using products that have been tested by a third party for potency and contaminants, such as pesticides.
As CBD is relatively new, many of the available products may not be what they appear, or may not have undergone quality control assessments.
Most CBD product websites should have a Certificate of Authenticity. We advise avoiding those that do not.
See our guide to top CBD oils here.
The FDA has approved one CBD product for use in two rare and severe forms of epilepsy. They have not currently approved any other CBD products for any purpose.
At this time, it is illegal to market CBD by labeling it as a dietary supplement or adding it to food.
Studies examining CBD to treat various conditions and diseases are still in the early stages, and more research is required to draw any conclusions.
Some CBD products are of unknown quality and marketed with unproven medical claims.
There is limited information about the risks and side effects of CBD.