Cannabidiol (CBD) oil contains substances (cannabinoids) that interact with specialized receptors in your body, triggering biochemical reactions. As a result, CBD oil may help relieve anxiety, improve sleep, support recovery from substance use disorders, and ease the symptoms of mental health conditions such as schizophrenia.
Scientific studies support CBD oil's effectiveness to varying degrees, with more research needed to verify most benefits. However, there's no doubt about its value for a specific condition: A prescription medication containing CBD, Epidiolex®, is FDA-approved to treat seizures that often begin in the first year of life.
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What Is CBD Oil and How Does It Work?
Cannabinoids are a large group of substances found in hemp and other plants in the Cannabis family, which includes marijuana. Oils are extracted from hemp to create the CBD oil used in over-the-counter products, such as oral liquids, gummies, capsules, and topical creams.
The cannabinoids in CBD oil interact with the body’s natural endocannabinoid system (ECS). Endocannabinoids are chemical messengers (neurotransmitters) that help regulate many crucial functions throughout your body, from mood, memory, and sleep to pain control and the immune response.
This widespread influence of the ECS is the reason CBD oil has the potential to affect different physical and mental health conditions.
By federal law, hemp-derived CBD oil must limit delta-9-tetrahydrocannabinol (THC) to 0.3% or less. As a result, you can't get "high" from CBD oil as you would when using marijuana (unless the product you purchase has more THC than the legal amount).
What Is CBD Used For?
CBD use should be individualized and vetted by a healthcare professional, such as a pharmacist or healthcare provider. OTC CBD oil products are not intended to treat, cure, or prevent disease.
Proponents of CBD oil claim that it benefits people with various health problems. As CBD has gained popularity, researchers have been trying to study it more—but, so far, human trials remain sparse. There is little evidence to support its myriad health claims.
Here's a deeper dive into CBD oil's more compelling health benefits.
Note that CBD oil is different from hemp oil. Hemp oil is processed differently (pressing hemp seeds) and typically contains no CBD.
Hemp oil can also refer to hemp seed oil, which is used for cooking, food production, and skincare products. CBD oil is made from the leaves, stems, buds, and flowers of the Cannabis indica or Cannabis sativa plant. It should contain less than 0.3% THC. Hemp oil is made from the seeds of Cannabis sativa and does not have TCH in it.
1. Supports Brain and Nerve Conditions
In June 2018, the FDA approved a CBD oral solution called Epidiolex. Epidiolex is a prescription drug, not an over-the-counter (OTC) product.
Epidiolex is used to treat two rare forms of epilepsy in children under 2 years: Dravet syndrome and Lennox-Gastaut syndrome. These rare genetic disorders cause lifelong seizures in the first year of life. It’s also approved for use in tuberous sclerosis complex, a rare genetic condition that causes benign tumors to grow throughout the body, often accompanied by seizures.
CBD has also been studied for the following:
While promising, further research is needed for these conditions. Note that OTC CBD products are not regulated or standardized like prescription medications such as Epidiolex.
2. May Help Treat Anxiety
CBD might help treat anxiety disorders, although there have not been many trials to look at CBD's anxiety-relieving effects in humans.
In one study, 57 men took either CBD oil or a sugar pill with no CBD (placebo) before a public speaking event. The researchers assessed the participants' anxiety levels using blood pressure and heart rate measures. The researchers also used a reliable test for mood states called the Visual Analog Mood Scale.
The men who took 300 milligrams (mg) of CBD oil reported less anxiety than the men who were given a placebo; however, the men who took 100 or 600 mg of CBD oil did not experience the same effects. This trial was limited by a small sample size and only enrolled men, so more data is needed to see if CBD has a similar impact on women.
In another double-blind placebo-controlled study (meaning neither participants nor researchers knew who took the substance and who took a placebo), CBD was also shown to decrease symptoms of social anxiety disorder in teenagers. This study was well-designed but very small; only 37 people were studied.
3. May Assist Substance Use Disorder Treatment
CBD may be able to inhibit the rewarding and reinforcing effects of addictive substances (e.g., tobacco, cocaine, methamphetamine (METH), heroin, and morphine). While the preliminary research is promising, more is needed to confirm results.
4. Might Help Treat Schizophrenia
In a randomized controlled trial of 88 people already taking medication for schizophrenia, 1,000 milligrams per day of CBD oil decreased positive psychotic symptoms (hallucinations or delusions). However, there were no significant differences between CBD oil and placebo regarding negative psychotic symptoms (like blunt affect or disinterest in others).
Also, note that CBD oil was studied as an add-on therapy here since the people in the trial were already taking prescription medicines to treat schizophrenia.
Products with significant amounts of THC may worsen symptoms of psychosis, schizophrenia, and paranoia.
5. May Support Sleep
There is conflicting evidence to support the use of cannabinoids to treat sleep disorders. Although some study outcomes have been favorable, most have not.
For example, a 2022 comprehensive review of the effects of cannabinoids on normal sleep and sleep disorders showed that cannabis products have minimal to no effects on sleep and may produce negative effects in some individuals.
A 2017 study found that CBD products containing THC may decrease the time needed to fall asleep. but could also impair sleep quality in the long term. And, a 2021 meta-analysis on CBD's effects as an appetite suppressant and as a sleep aid concluded that, while there was a moderate positive impact on appetite control, CBD showed no effect on sleep.
Despite underwhelming sleep results, research is ongoing to explore specific pharmacological properties and strengths of cannabinoids that might produce the soporific (inducing drowsiness) results often theorized. However, considering the absence of hard evidence, one study puts it best by advising: "Individuals seeking cannabis-derived sleep aids should be skeptical of manufacturers' claims of sleep-promoting effects."
6. May Lower High Blood Pressure
CBD may produce favorable outcomes for people attempting to lower their blood pressure. Multiple recent studies have shown CBD's effectiveness in reducing blood pressure in those with hypertension.
Accumulated data (both from human and animal studies) suggest that CBD may be associated with improved cardiovascular function and marked reductions in blood pressure. CBD may improve blood pressure by relaxing blood vessels and preventing damage to the tissues lining the vessel walls (endothelium).
7. Other Uses Being Studied
Although the data is preliminary, CBD oil has also been studied for the following uses:
- Acne
- Arthritis
- Chronic pain
- Digestive disorders
- Skin conditions (e.g., eczema and psoriasis)
There’s not enough data to recommend CBD oil for any of these uses quite yet.
CBD Oil vs. Marijuana | |
---|---|
CBD Oil | Marijuana |
A component of the hemp plant | Separate plant in the hemp family that contains CBD and hundreds of other compounds |
No or trace amounts of THC (0.3% or less) | Significant amounts of THC |
Works receptors in the brain, but not those that induce psychoactive effects (e.g., opioid receptors that help control pain, glycine receptors that impact mood control) | THC binds to cannabinoid receptors in the brain to create a "high" feeling |
Side Effects
Clinical research has shown that CBD oil can cause side effects. In one study, 91% of people with seizure disorders who took the prescription product Epidiolex had side effects from the medicine. The specific side effects and their severity vary from one person to the next and from one type of CBD to another.
Common Side Effects
The most common side effects of CBD oil that were reported include the following:
- Change in appetite
- Drowsiness or fatigue
- Diarrhea
- Change in liver enzymes
Severe Side Effects
Severe side effects have been noted in people with treatment-resistant epilepsy (ongoing seizures despite multiple medications). These include:
- Status epilepticus (a life-threatening medical emergency where a seizure lasts longer than five minutes)
- Pneumonia (infection of the air sacs in the lungs)
Also, consider that CBD products are not regulated and may be adulterated or labeled misleadingly. One study found that 21% of CBD products sold online also had THC. Severe side effects of THC, particularly at doses above 2.4 mg, can be quite severe and include:
- Anxiety
- Impaired cognition (lowered IQ scores and memory loss)
- Psychosis (including suspiciousness, emotional withdrawal, and hallucinations)
If you notice these effects while using CBD oil, discontinue and discuss side effects with a healthcare provider as soon as possible.
Adolescent users are at increased risk of psychological disorders from THC. These include an increased risk of psychosis and schizophrenia.
Do not drive or use heavy machinery when taking CBD oil—especially when you first start using it or switch to a new brand. Remember that some products do contain THC, even in small amounts.
Precautions
Your healthcare practitioner may advise against using CBD oil if you:
- Have liver disease: CBD oil may increase liver enzymes, a marker of liver inflammation. Talk with your healthcare provider before taking CBD oil if you have liver disease. You may need to check your liver enzymes regularly if you use CBD.
- Have eye issues: CBD oil may also cause eye-related side effects. A 2018 study found that it may increase pressure inside the eyes. For people with glaucoma, this can make the condition worse. Some people also report dry eyes as a side effect of CBD oil.
- Are pregnant or nursing: You should not use CBD oil if you're pregnant or breastfeeding. Even though the effects of CBD are not fully understood, it does pass through the placenta. The American Academy of Pediatrics (AAP) further states that pregnant people should not use marijuana products because of the potential risks to developing fetuses.
- Drink alcohol or take other sedating medications: Using CBD with these drugs could cause excess drowsiness.
- Are a child: Children should not use CBD oil.
Product Facts
- Active ingredient(s): Cannabidiol
- Alternate name(s): Cannabis, Cannabis ruderalis extract, hemp plant extract
- Legal status: Prescription drug (Epidiolex), legal in most states; not considered a dietary supplement by the FDA (FD&C Act)
- Suggested dose: Varies based on condition. CBD is not meant to prevent, treat, or cure disease.
- Safety considerations: Contraindicated in pregnancy and breastfeeding and not for use in children. Interacts with alcohol and many prescription medications.
How to Take It Safely
Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs.
There are no dosing standards for CBD products. Additionally, the dose you may need varies depending on the reason for using CBD oil and your age. Consider the following as two general guidelines:
- Adults: Doses up to 200 mg daily for up to 13 weeks may be safe
- Children: Children should not use CBD oil unless prescribed by their healthcare provider
The label on CBD oil products may show the amount of CBD per dose. However, there are no guarantees that they contain the ingredients and doses stated on the label. The potential danger is that you can't know if you're getting more or less CBD.
Taking too much CBD may cause mild to severe side effects that need immediate medical attention. If you or your child develop side effects or you have questions or concerns, take one of the following steps:
- Call your healthcare provider.
- Call the Poison Control Center at 800-222-1222.
- Call 911 for emergency care.
Interactions
CBD oil can interact with medications, including many used to treat epilepsy. One of the reasons for this has to do with how the body breaks down (metabolizes) drugs.
Cytochrome P450 (CYP450) is a liver enzyme your body uses to break down some drugs. CBD oil is broken down by and can also affect CYP450. That means taking CBD oil with these drugs could have a more substantial effect than you need or reduce their efficacy.
Drugs that could potentially interact with CBD include:
- Anticonvulsants like phenobarbitol, topiramate, Lamictal (lamotrigine), Onfi (clobazam), Dilantin (phenytoin), Tegretol (carbamazepine) and Trileptal (oxcarbazepine). CBD oil lowers the effectiveness of many anticonvulsant medications used to treat epilepsy. However, it may enhance the impact of others.
- Antidepressants like Paxil (paroxetine), Celexa (citalopram), Remeron (mirtazapine), and Tofranil (imipramine). CBD may increase the levels of these medicines and exacerbate their side effects.
- Antifungals like ketoconazole. CBD interferes with some antifungals and boosts the effect of others.
- Macrolide antibiotics like clarithromycin. Like antifungals, CBD oil may either increase or decrease the effect of antibiotics, depending on the specific drug.
- Antipsychotics like Haldol (haloperidol). CBD oil may increase blood levels of antipsychotics, raising the risk of side effects ranging from mild to severe (movement and heart problems).
- Benzodiazepine sedatives like Klonopin (clonazepam), Ativan (lorazepam), and Valium (diazepam). CBD decreases the effect of clonazepam and increases the impact of the others, which may increase side effects like drowsiness.
- Erectile dysfunction drugs like Viagra (sildenafil). CBD oil raises blood levels of erectile dysfunction drugs, causing side effects like a drop in blood pressure.
- Immune-suppressants like Sandimmune (cyclosporine). CBD may increase the levels of these drugs.
- Opioid painkillers like morphine. CBD increases the effect of morphine.
- Statins to treat cholesterol like Lipitor (atorvastatin) and Zocor (simvastatin). CBD raises the risk of uncommon statin side effects like muscle pain.
Always tell your healthcare provider and pharmacist about all your medicines, including prescription, OTC, herbal, or recreational drugs. Alcohol or other recreational drugs that cause drowsiness may have increased side effects if used with CBD oil.
The interactions between these medications and CBD may be mild, and you might not have to change your treatment. However, in some cases, you might have to avoid CBD oil or change drug dosages to avoid a reaction. Never change or stop medication without talking to your provider.
It is essential to read the label and ingredient list on CBD products and consult with your healthcare provider to discuss potential interactions with supplements, medications (over-the-counter and prescription), and food. While you can take CBD products with or without food, your body may absorb more CBD with food, increasing its effects and interactions.
Is CBD oil legal in all states?
Federal law allows the sale of hemp-based CBD oil (with 0.3% or less THC content) in all states. However, each state can regulate these products as it wishes.
Though CBD oil (from hemp) is currently legal in all states, the laws can change to restrict or expand its uses. For example, some states may not allow it to be sold to minors.
The FDA, which has the authority to regulate all cannabis compounds, including those derived from hemp, does not allow CBD products to be marketed as dietary supplements.
Sources of CBD Oil and What to Look For
CBD can be derived from two types of cannabis plants: marijuana, which has a higher amount of THC, and hemp, which has a low amount of THC. Since 2018, the FDA has allowed CBD products to be sold as long as they have less than 0.3% THC.
You can also get CBD oil in several forms:
- Isolates contain only CBD.
- Broad-spectrum oils have nearly all of the components of the plant (e.g., proteins, flavonoids, terpenes, and chlorophyll) but do not have THC.
- Full-spectrum oils have all the compounds, including THC (up to 0.3%)
While some believe that broad- and full-spectrum products provide more health benefits, there's a lack of evidence to support these claims.
Remember that CBD oils are unregulated. There's no guarantee that a product is what it claims to be on its packaging. You also can't know for sure that it's safe and effective.
How can I verify CBD oil quality?
Verifying the quality of CBD oil is essential. A 2017 study reported that only 31% of CBD products sold online were correctly labeled. Most had less CBD in them than was advertised, and 21% had significant amounts of THC.
Choose products with a certificate of analysis (COA) from an independent lab and/or from companies with current Good Manufacturing Practices (cGMP) certification. The COA means that the product has been tested for CBD and THC levels, along with possible contaminants. Because CBD comes from a plant, it is susceptible to chemicals like pesticides.
If possible, make sure the lab making the product meets ISO 17025 standards, which shows high scientific standards are met.
Summary
CBD oil is extracted from the hemp plant, a member of the cannabis family that includes marijuana. The oil contains active ingredients that cause biochemical responses in your body, leading to many potential health benefits.
Taking CBD oil may ease anxiety, help you sleep, improve high blood pressure, and relieve symptoms of mental health conditions like substance use disorders and schizophrenia. A prescription medication containing CBD is used to treat epilepsy.
The amount of THC in CBD oil is limited, so you won’t get high. However, CBD can cause side effects, including fatigue, diarrhea, and a change in your appetite.
CBD oil can also interact with dietary supplements and medications (over-the-counter and prescription), making them more or less effective. Consult with your healthcare provider to avoid potentially serious side effects caused by these interactions. Children and women who are pregnant or breastfeeding should not use CBD oil products.