What Is CBD Oil?

This cannabis extract may help treat nerve pain, anxiety, and epilepsy

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CBD oil is an extract of Cannabis indica and Cannabis sativa, the same plants used to make marijuana.

CBD oil may treat pain, lower anxiety, and stimulate appetite the same way that marijuana does, but without affecting your mental state. CBD might also help treat some types of seizures.

CBD is the short name for cannabidiol, one of the two chemicals in cannabis with the most health benefits. The other chemical is tetrahydrocannabinol (THC).

THC is what's responsible for the psychoactive effects of cannabis—in other words, what makes you feel "high." CBD oil generally doesn't have THC, although trace amounts might be in products sold in certain states.

CBD oil contains CBD mixed with a base (carrier) oil, like coconut oil or hemp seed oil. The bottled CBD oil is called a tincture and is sold in different concentrations.

There are also CBD capsules, CBD gummies, and under-the-tongue CBD sprays.

This article goes over what CBD is used for, possible side effects, and what you should look for if you choose to buy CBD.

Conditions that CBD oil may help to improve
Verywell / Brianna Gilmartin

What Is CBD Oil Used For?

CBD's exact mechanism of action is unclear.

Unlike THC, CBD doesn't have a strong connection with cannabinoid receptors in the brain. These are the molecules that THC binds to create psychoactive effects.

Instead, CBD influences other receptors, like the opioid receptors that control pain. It also affects glycine receptors. These control serotonin, a brain chemical known as the "feel-good" hormone.

People that support the use of CBD claim that CBD oil can treat a variety of health problems, including:

More research on CBD has been emerging as it has gained popularity. Still, there are only a few clinical studies on the effects of CBD oil.

As such, some of these health claims are better supported by research than others.

If you're thinking of using CBD oil to treat a health condition, talk to your healthcare provider to make sure it's an appropriate option for you.

Anxiety

A 2015 review of studies in the journal Neurotherapeutics suggests that CBD might help treat anxiety disorders.

The study authors report that CBD had powerful anxiety-relieving effects in animal research. But the results weren't what you'd expect.

In most of the studies, lower doses of CBD (10 milligrams per kilogram, mg/kg, or less) improved some symptoms of anxiety, but higher doses (100 mg/kg or more) had almost no effect.

The way that CBD acts in the brain can explain why this happens. In low doses, CBD may act the same as surrounding molecules that normally bind to the receptor, which "turns up" their signaling.

However, at higher doses, too much activity at the receptor site can lead to the opposite effect. This would take away the helpful effects of CBD.

There aren't many study trials that look at CBD's anxiety-relieving effects in humans. One of the few is a 2019 study published in the Brazilian Journal of Psychiatry.

For the study, 57 men took either CBD oil or a placebo (sugar pill) before a public-speaking event. The researchers based anxiety levels on measures like blood pressure and heart rate. They also used a fairly reliable test for mood states called the Visual Analog Mood Scale (VAMS).

The men who took 300 mg of CBD oil showed less anxiety than those given a placebo. Interestingly, the men who took 100 mg or 600 mg of CBD oil didn't have these results.

Addiction

CBD oil might help people with substance use disorder, per a 2015 review in the journal Substance Abuse.

The review analyzed 14 published studies. Nine of the studies looked at the effects on animals, and five studies looked at the effects on humans.

The researchers reported that CBD showed promise in treating people with opioid, cocaine, or psychostimulant addiction.

However, CBD affected each type of addiction very differently.

For example, CBD without THC didn't help decrease withdrawal symptoms of opioid use. On the other hand, it did reduce drug-seeking behaviors in users of cocaine, methamphetamine, and other similar drugs.

Some experts suggest CBD may help treat cannabis and nicotine dependence, but more research is needed.

Nerve Pain

Doctors may prescribe medical marijuana to people with pain that's resistant to treatment, like those with terminal cancer. There's some evidence that CBD plays a role in this benefit.

One interesting piece of research is a 2012 study published in the Journal of Experimental Medicine. Researchers injected rats with chemicals that prompt inflammation. Then they gave the rats CBD.

The rats that got CBD experienced less inflammation and nerve pain (pain caused by damage to your nerves).

Scientists believe CBD reduces nerve pain by binding to receptors in the brain that control the speed at which nerve signals pass between nerve cells.

However, there aren't many studies that examine the use of CBD in treating chronic pain in people. The studies that do exist almost always include THC. This makes it hard to isolate CBD's unique effects.

High Blood Pressure

CBD oil may reduce the risk of heart disease by relieving high blood pressure in some people, per a 2017 study in JCI Insight.

For the study, nine healthy men took either 600 mg of CBD or the same dose of a placebo. The men who took CBD had lower blood pressure before and after stressful things, like exercise or extreme cold.

The study also looked at stroke volume (the amount of blood remaining in the heart after a heartbeat). The stroke volume in the men who took CBD was lower than that in the placebo group, meaning the heart was pumping more efficiently.

The study suggests CBD oil may be a good complementary therapy for people whose high blood pressure is affected by stress and anxiety.

However, there's no evidence CBD oil can treat high blood pressure on its own or prevent it in people at risk. While stress can complicate high blood pressure, it can't cause it.

Seizures

In June 2018, the U.S. Food and Drug Administration (FDA) approved Epidiolex, a CBD oral solution.

Epidiolex is used to treat two rare forms of epilepsy in children under 2: Dravet syndrome and Lennox-Gastaut syndrome. These are very rare genetic disorders that cause lifelong seizures that start in the first year of life.

Outside of these two disorders, CBD's effectiveness in treating seizures is uncertain. Even with Epidiolex, it's unclear if the anti-seizure effects are from CBD or some other factor.

There's some evidence CBD interacts with seizure medicines like Onfi (clobazam) and boosts their concentration in the blood. More research is needed, though.

Recap

CBD oil might help relieve stress, anxiety, seizures, drug withdrawal, and nerve pain. But taking higher doses doesn't always mean they'll have a stronger impact. Also, many studies on CBD have been done on animals, so it's hard to tell if these same effects will apply to people.

Possible Side Effects

Clinical research has shown that CBD oil can trigger side effects. The severity and type can vary from one person to the next.

Common side effects include:

  • Anxiety
  • Changes in appetite
  • Changes in mood
  • Diarrhea
  • Dizziness
  • Drowsiness
  • Dry mouth
  • Nausea
  • Vomiting

CBD oil may also increase liver enzymes (a marker of liver inflammation). People with liver disease should consult their healthcare provider before taking CBD oil and use it with caution. Regular blood liver enzyme level checks are recommended.

Don't take CBD oil if you're pregnant or breastfeeding. The American Academy of Pediatrics advises pregnant women to avoid marijuana because of the potential risks to a baby's development. Although the effects of CBD itself are unclear, CBD does pass through the placenta.

Don't drive or use heavy machinery when taking CBD oil since some of them contain THC. This is especially important when you first start treatment or use a new brand.

Interactions

CBD oil can interact with some medications, including those used to treat epilepsy.

Cytochrome P450 (CYP450) is an enzyme in your body that breaks down certain drugs. But CBD oil can block CYP450 from working the way it normally does. CBD oil can either make some drugs you take have a stronger effect than you need or make them less effective.

Drugs that could potentially interact with CBD include:

  • Anti-arrhythmia drugs like quinidine
  • Anticonvulsants like Tegretol (carbamazepine) and Trileptal (oxcarbazepine)
  • Antifungal drugs like Nizoral (ketoconazole) and Vfend (voriconazole)
  • Antipsychotic drugs like Orap (pimozide)
  • Atypical antidepressants like Remeron (mirtazapine)
  • Benzodiazepine sedatives like Klonopin (clonazepam) and Halcion (triazolam)
  • Immune-suppressive drugs like Sandimmune (cyclosporine)
  • Macrolide antibiotics like clarithromycin and telithromycin
  • Migraine medicine like Ergomar (ergotamine)
  • Opioid painkillers like Duragesic (fentanyl) and alfentanil
  • Rifampin-based drugs used to treat tuberculosis

To avoid interactions, tell your healthcare provider and pharmacist what medicine you're taking. This includes prescription, over-the-counter, herbal, or recreational drugs.

Many of these interactions are mild and don't demand a change to treatment. Others may require you to substitute the drugs you are taking or to separate doses by several hours.

Of course, never make changes to your medication regimen without your doctor's OK.

Recap

You might experience nausea, diarrhea, or dizziness when you take CBD oil. Don't take CBD oil if you're pregnant or breastfeeding. Also, CBD oil affects the way your body breaks down certain drugs, so talk to your healthcare provider if you're on any medications.

Dosage and Preparation

There are no guidelines for the proper use of CBD oil. CBD oil is usually taken by placing one or more drops under the tongue and holding it there for 30 to 60 seconds without swallowing.

There's no known "correct" dose of CBD oil. Depending on your needs and what you're treating, the daily dose may range between 5 mg and 25 mg.

The tricky part is calculating the exact amount of CBD per milliliter of oil. Some tinctures have concentrations of 1,500 mg per 30 mL, while others have 3,000 mg per mL (or more).

Most oils come in 30-milliliter (mL) bottles with a dropper cap.

How to Calculate CBD Dose

To determine an exact dose of CBD, remember that each drop of oil equals 0.05 mL of fluid. This means that a 30-mL bottle of CBD oil will have about 600 drops. If the concentration of the tincture is 1,500 mg per mL, one drop would contain 2.5 mg of CBD (1,500 mg ÷ 600 drops = 2.5 mg).

Capsules, gummies, and sprays are easier to dose, although they tend to be more expensive.

What to Look For

CBD oil comes in different forms. Isolates contain only CBD, but full-spectrum oils have several compounds from the cannabis plant. This includes proteins, flavonoids, terpenes, and chlorophyll.

Alternative medicine practitioners believe these compounds provide more important health benefits, but there's no clear evidence to support this.

Remember that CBD oils are mostly unregulated, so there's no guarantee that a product is safe, effective, or what it claims to be on its packaging.

A 2017 study reported that only 31% of CBD products sold online were correctly labeled. Most contained less CBD than advertised, while 21% had significant amounts of THC.

Here are a few tips to help you find the best CBD oil:

  • Buy American: Domestically produced CBD oil may be safer.
  • Go organic: Brands certified organic by the U.S. Department of Agriculture (USDA) are less likely to expose you to pesticides and other harmful chemicals.
  • Read the product label: Even if you choose a full-spectrum oil, don't assume that every ingredient on the product label is natural. There may be preservatives, flavorings, or thinning agents that you don't want or need. If you don't recognize an ingredient, ask the dispenser what it is or check online.

Are CBD Oil and Hemp Oil the Same?

Not necessarily. While some use these names interchangeably, hemp oil might also be used for 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 and should contain less than 0.3% THC. Hemp oil is made from the seeds of Cannabis sativa and contains no TCH.

Summary

Unlike the THC that's in marijuana, CBD oil doesn't get you high. It contains a chemical called cannabidiol that might help relieve stress, anxiety, drug withdrawals, and nerve pain.

However, CBD oil might change the way your body breaks down certain medications. This could make the drugs have a stronger or weaker effect, which can be dangerous. Talk to your doctor before you use CBD oil, especially if you take any medicine or have liver disease.

Frequently Asked Questions

  • Is it possible to overdose on CBD oil?

    It would be hard to overdose on CBD oil because human tolerance is very high. One study reported the toxic dose would be about 20,000 mg taken at one time.

  • How old do you have to be to buy CBD oil?

    It depends on where you live, the form of the product, how it was sourced (via hemp or marijuana), and its intended purpose (medical or recreational). In many states, you must be 18 or 21 to buy CBD oil. Check your state's laws.

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