What is Epidiolex? Plus, 7 More Epidiolex FAQs

Epidiolex (cannabidiol) is an oral liquid medication that treats certain types of seizures in adults and children. You may have heard of Epidiolex as being an FDA-approved cannabis medication. But what is Epidiolex, and is it the same thing as the CBD sold over the counter?

Here, we’ll look at the answers to these and other frequently asked questions about Epidiolex.

1. What is Epidiolex?

Epidiolex is an anti-seizure medication. But it’s only approved for three specific types of seizure-related conditions: Lennox-Gastaut syndrome, Dravet syndrome, and tuberous sclerosis complex.

Epidiolex is approved for adults and children ages 1 year and older. The conditions it treats typically start in early childhood, so Epidiolex comes as a liquid to make it easier for young children to swallow.

The active ingredient in Epidiolex is cannabidiol, often referred to as CBD. CBD is a chemical found in the cannabis plant. Epidiolex contains CBD that’s been extracted from cannabis plants and purified. It’s the only natural cannabis-based medication that’s been approved by the FDA.

2. How does Epidiolex work?

Epidiolex can affect several different types of receptors (binding sites) in the body. Still, it’s not entirely clear how Epidiolex works to treat seizures.

Much of the interest in CBD as a seizure treatment came from parents seeking alternative options when traditional medications didn’t work for their child’s seizure condition. People started reporting a large reduction in seizures when they used CBD. As a result, clinical studies were set up to determine if CBD was in fact an effective seizure treatment and, if so, what dosage was safe and effective. Those studies were the basis of Epidiolex’s development.  

3. Is Epidiolex the same thing as CBD?

Yes, and also no. Epidiolex contains cannabidiol (CBD), which is the same chemical found in other CBD products. But they’re very different products when it comes to safety and their approved uses.

As mentioned, Epidiolex is an FDA-approved medication. This means Epidiolex has clinical studies proving that it’s a safe and effective treatment option. It also has clear dosing guidelines and safety information. What’s more, Epidiolex is required to follow strict manufacturing guidelines to ensure that every batch of medication is the same and doesn’t contain any contaminants.

Other CBD products aren’t approved for any medical use. And they don’t have proven dosing guidelines and safety information, either. OTC CBD products also aren’t well regulated when it comes to how they’re made. It’s common for CBD products to contain more or less CBD than the label says. And they can contain contaminants and other unsafe ingredients, too. Some OTC CBD products contain synthetic (lab-made) CBD, too.

Can you take CBD instead of seizure medications?

You shouldn’t try to replace your seizure medications with CBD. In most cases, even Epidiolex is only prescribed if traditional prescription medications aren’t successful. If your current medications are working well to control your seizures, it’s best to keep taking them. If there’s a reason you’d prefer to stop taking them, such as side effects, talk to your prescriber. They may be able to adjust your dose or make other medication changes to help.

If prescription medications aren’t working well for your seizures, you shouldn’t try taking CBD on your own. It can interact with other medications you’re taking and cause side effects. Talk to your prescriber first to determine if CBD is a safe option for you. And keep in mind that it’s only been proven effective for the three types of seizures mentioned earlier, so it may not work for you if you have a different type of seizure condition. 

4. How long does it take Epidiolex to work?

In clinical studies, Epidiolex started working within 4 weeks of starting the medication. The Epidiolex dosage is increased slowly to minimize side effects. So in some cases it may take longer for it to start working, depending on how quickly the dose is increased.

5. Does Epidiolex make you feel ‘high’?

No. Epidiolex doesn’t make you feel high. Tetrahydrocannabinol (THC) is the active ingredient in cannabis that produces a high. And Epidiolex doesn’t contain a significant amount of THC. There also isn’t any evidence that it leads to misuse or dependence.

That being said, high doses of CBD can make you feel drowsy, which is a common Epidiolex side effect. Slowly increasing the dose of Epidiolex can help minimize drowsiness, and it typically improves over time as your body adjusts to the medication.

6. Does Epidiolex cause weight changes?

Epidiolex may cause a small amount of weight loss in some people. Common Epidiolex side effects include nausea, diarrhea, and loss of appetite, which can contribute to weight loss. It also seems to be dose-related, with more potential weight loss as the Epidiolex dose goes up.

Eating smaller meals throughout the day can help lessen nausea and help you get the nutrition your body needs to maintain a healthy weight. Nutritional drinks, such as Pediasure, can also help children maintain growth and development if they aren’t eating enough. If you’re concerned about weight loss with Epidiolex, talk to your prescriber. They may be able to adjust your dose to help

7. How long does Epidiolex stay in your system?

Epidiolex stays in your system for quite a while after you stop taking it. It can take almost 2 weeks to fully clear it from your body.

But you shouldn’t stop taking Epidiolex on your own. Suddenly stopping a seizure medication such as Epidiolex could cause dangerous rebound seizures. If your prescriber decides it’s OK for you or your child to stop taking Epidiolex, they’ll give you instructions for doing so safely.

8. Is Epidiolex safe to take?

Yes. Epidiolex is considered a safe and effective medication if it’s taken as directed.

As with any medication, mild side effects are common. These include nausea, diarrhea, and drowsiness. Increased liver enzymes are also possible, but that typically resolves on its own or once a drug interaction is resolved. Rare but serious side effects include suicidal thoughts and low blood cell counts. 

How to save on Epidiolex

 There are ways to save on Epidiolex, which is only available as a brand-name medication. GoodRx can help you navigate between patient assistance programs and copay savings cards to save money on your prescription.

• Save with a copay savings card. If you have commercial insurance, you may be eligible to pay as little as $0 for Epidiolex using a savings card from the manufacturer.

• Save with specialty programs. You may be able to receive 60 days of Epidiolex at no cost while you’re waiting for insurance approval. And you can receive a 30-day supply of Epidiolex at no cost if you’re sent home from the hospital before you can get a prescription filled to use at home. Your healthcare team can help you enroll in these programs if you’re eligible.

• Save with patient assistance programs. If you’re uninsured or underinsured, you may be eligible for Epidiolex’s patient assistance program, which offers the medication at no cost.

Good to know: Epidiolex is a limited distribution drug, which means not every pharmacy carries it. You’ll likely need to have your prescription filled at a specialty pharmacy, and it may take longer than usual to set up the prescription and receive the medication. The good news is that specialty pharmacies will often go the extra mile to help you get insurance approval and/or take advantage of discounts and programs to help you afford your medication.

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Written by:

Alex Evans, PharmD, MBA

Alex Evans, PharmD, MBA, has been a pharmacist for 12 years. His first job was floating in a community chain pharmacy.

Edited by:

Stacia Woodcock, PharmD

Stacia Woodcock, PharmD, is a pharmacy editor for GoodRx. She earned her Doctor of Pharmacy degree from the University of Kentucky and is licensed in New York and Massachusetts.

Reviewed by:

Tegan Smedley, PharmD, APh

Tegan Smedley, PharmD, APh, has 10 years of experience as a pharmacist. She has worked in a variety of settings, including retail, hospital, and ambulatory care.

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