Epidiolex (cannabidiol) is a brand-name oral solution. It’s prescribed for adults and some children with certain seizure conditions. As with other drugs, Epidiolex can cause side effects. These include liver problems and digestive problems.

Epidiolex can cause certain side effects, some of which are more common than others. These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

These are just a few of the more common side effects reported by people who took Epidiolex in clinical trials:

Mild side effects can occur with Epidiolex use. This list doesn’t include all possible mild side effects of the drug. For more information, you can refer to Epidiolex’s prescribing information.

Mild side effects that have been reported with Epidiolex include:

These side effects may be temporary, lasting a few days to weeks. However, if the side effects last longer than that, bother you, or become severe, be sure to talk with your doctor or pharmacist.

Note: After the Food and Drug Administration (FDA) approves a drug, it tracks and reviews side effects of the medication. If you develop a side effect while taking Epidiolex and want to tell the FDA about it, visit MedWatch.

* To learn more, see the “Side effect specifics” section below.

Epidiolex may cause serious side effects. The list below may not include all possible serious side effects of the drug. For more information, you can refer to Epidiolex’s prescribing information.

If you develop serious side effects while taking Epidiolex, call your doctor right away. If the side effects seem life threatening or you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Serious side effects that have been reported and their symptoms include:

* For more information about this side effect, see “Side effect specifics” below.
† To learn more, see the “Side effect specifics” section below.

Epidiolex may cause several side effects. Here are some frequently asked questions about the drug’s side effects and their answers.

How do side effects of Epidiolex compare with those seen with clobazam?

Epidiolex and clobazam (Onfi, Sympazan) are prescribed for seizures related to certain conditions. Specifically, either drug can be prescribed to treat a rare type of epilepsy called Lennox-Gastaut syndrome.

Both drugs can cause side effects such as sleepiness, insomnia, and vomiting. In addition, both drugs increase the risk of suicidal thoughts or behaviors.

Clobazam may cause other side effects that aren’t known to occur with Epidiolex. For example, clobazam has several boxed warnings. A boxed warning is the most serious warning from the Food and Drug Administration (FDA). For clobazam, these include:

For more information about how Epidiolex’s side effects compare with clobazam’s, talk with your doctor or pharmacist.

Is Epidiolex safe for older adults?

Yes, Epidiolex is generally considered safe for older adults (ages 65 years and older).

However, older adults may be more likely to have certain health conditions affecting how their bodies respond to Epidiolex. For this reason, doctors may prescribe a lower dosage of Epidiolex for older adults than for younger people. To learn more about dosages for Epidiolex, see this article.

For details about whether Epidiolex is safe given your age, talk with your doctor or pharmacist.

Learn more about some of the side effects that Epidiolex may cause. To find out how often side effects occurred in clinical trials, see the prescribing information for Epidiolex.

Liver problems

High liver enzyme levels were common in clinical trials of Epidiolex. An increase in liver enzyme levels may be a sign of liver problems.

High liver enzyme levels may not cause symptoms but can be detected with a blood test. Certain other liver problems may cause loss of appetite, abdominal pain, and jaundice.

Certain factors may increase your risk of liver problems with Epidiolex. These include taking higher doses or taking Epidiolex with other medications that cause liver problems, such as:

What you can do

Before starting treatment with Epidiolex, be sure to tell your doctor about any medications you take. They can advise whether it’s safe for you to take Epidiolex with these medications.

Your doctor will likely give you blood tests to check your liver enzyme levels before you start taking Epidiolex. They’ll continue to monitor your liver enzymes while you take the drug. Tell your doctor right away if you have symptoms of liver problems while taking Epidiolex.

If you have high liver enzymes or symptoms of liver problems, your doctor may lower your dosage of the drug. To learn more about dosages for Epidiolex, see this article.

Sedation

Sedation was a common side effect in clinical trials of Epidiolex. With sedation, you may feel calm, relaxed, or sleepy. This side effect usually occurs when you first start Epidiolex treatment. However, it typically eases as your body gets used to the drug.

Certain factors can increase your risk of sedation with Epidiolex. These include taking the drug with alcohol or certain other medications, such as benzodiazepines.

What you can do

Sedation with Epidiolex may lead to difficulties with thinking, coordination, or judgment. Due to this risk, it’s important to avoid driving after a dose until you know how Epidiolex affects you. It may take several doses before you know how the drug will affect you.

If you experience sedation during treatment that’s severe or bothersome, talk with your doctor. They can suggest other ways to manage this side effect.

Allergic reaction

As with most drugs, Epidiolex can cause an allergic reaction in some people. In clinical trials, this side effect wasn’t common.

Symptoms can be mild or serious and can include:

  • skin rash
  • itching
  • flushing
  • swelling under your skin, typically in your eyelids, lips, hands, or feet
  • swelling of your mouth, tongue, or throat, which can make it hard to breathe

What you can do

For mild symptoms of an allergic reaction, call your doctor right away. They may recommend ways to ease your symptoms and determine whether you should keep taking Epidiolex. However, if your symptoms are serious and you think you’re having a medical emergency, immediately call 911 or your local emergency number.

Suicide prevention

If you know someone at immediate risk of self-harm, suicide, or hurting another person:

  • Ask the tough question: “Are you considering suicide?”
  • Listen to the person without judgment.
  • Call 911 or the local emergency number, or text TALK to 741741 to communicate with a trained crisis counselor.
  • Stay with the person until professional help arrives.
  • Try to remove any weapons, medications, or other potentially harmful objects if it’s safe to do so.

If you or someone you know is having thoughts of suicide, a prevention hotline can help. The 988 Suicide and Crisis Lifeline is available 24 hours a day at 988. During a crisis, people who are hard of hearing can use their preferred relay service or dial 711 then 988.

Find more links and local resources.

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Be sure to talk with your doctor about your health history before you take Epidiolex. This drug may not be the right treatment for you if you have certain medical conditions or other factors that affect your health. These are considered drug-condition or drug-factor interactions. The conditions and factors to consider include:

Liver problems. Before taking Epidiolex, tell your doctor if you have any liver problems. These include liver disease and liver failure. Epidiolex can cause liver problems and may worsen any existing liver conditions.

In addition, certain liver problems can cause Epidiolex to build up in your system. High levels of this drug in your body may increase your risk of side effects. For this reason, your doctor may prescribe a lower dosage of Epidiolex if you have certain liver problems. This can help reduce your risk of side effects.

Mood changes, including suicidal thoughts or behaviors. Epidiolex may cause mood changes, including depression and suicidal thoughts or behaviors. Before starting treatment, tell your doctor if you have a condition that affects your mood. They can tell you whether Epidiolex is a safe treatment option.

Allergic reaction. If you’ve had an allergic reaction to Epidiolex or any of its ingredients, including sesame seed oil, your doctor will likely not prescribe Epidiolex. Ask your doctor what other medications may be better options for you.

Pregnancy or breastfeeding. If you’re pregnant or breastfeeding your child, Epidiolex may not be safe for your pregnancy or child. Please talk with your doctor before taking Epidiolex.

If you take Epidiolex during pregnancy, ask your doctor about enrolling in a pregnancy registry. The North American Antiepileptic Drug Pregnancy Registry looks at how antiepileptic drugs, such as Epidiolex, may affect pregnancy. To learn more, visit the registry’s website or call 888-233-2334.

Alcohol consumption. If you drink alcohol, Epidiolex may not be safe for you to take. Drinking alcohol while taking the drug could increase your risk of sleepiness and sedation. If you have questions about drinking alcohol while taking Epidiolex, talk with your doctor or pharmacist. They may recommend that you do not drink alcohol while taking this drug.

Epidiolex may cause mild and serious side effects. If you have bothersome or long lasting side effects with Epidiolex, talk with your doctor or pharmacist.

If you’d like to learn more about Epidiolex, talk with your doctor or pharmacist. They can help answer any questions you have about side effects from taking the drug.

Besides talking with your doctor, you can do some research on your own. These articles might help:

  • More information about Epidiolex. For details about other aspects of Epidiolex, refer to this article.
  • Cost. If you’d like to learn about Epidiolex and cost, see this article.
  • Drug comparison. To learn how Epidiolex compares with Charlotte’s Web, read this article.
  • Dosage. For information about the dosage of Epidiolex, view this article.
  • A look at CBD and seizures. For details about seizures, see our epilepsy and seizures hub. For more information about CBD, see our CBD hub.

Disclaimer: Medical News Today has made every effort to make certain that all information is factually correct, comprehensive, and up to date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or another healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.