Skip to main content

Does CBD Interact With Medications: What to Know

Does CBD Interact With Medications: What to Know

Cannabidiol (CBD) offers many therapeutic benefits for a wide variety of common ailments. But if you’re suffering from certain conditions, it’s important to be aware of how CBD works in the body. For instance, does CBD interact with medications you might be taking?Indeed, CBD can interact with several common medications. With some, it even has the potential to interfere with the drugs’ effectiveness, either requiring a modified dosage or entirely preventing the drug’s efficacy!

In this article, we break down what you need to know about this important question. We dive into CBD’s most common potential drug interactions, cover how CBD works on the physiological level, and discuss why it’s so important to talk to your doctor about CBD and your prescription medications.

The Grapefruit Test

CBD isn’t the only substance that can interfere with the efficacy of prescription drugs. Many common substances, or even foods you eat every day, can reduce the effectiveness of prescription or over-the-counter (OTC) medications.

One of the most common? Grapefruit.

And for CBD users, that’s actually a useful metric, as CBD interacts with drugs in the same way that grapefruit does.

As such, CBD users should be careful to double-check whether their medications are safe to take with grapefruit. If so, then CBD should not interfere with your prescription. If not, then CBD could get in the way of your drug’s efficacy, and alternative treatments should be discussed with your physician.

Which Drugs Does CBD Interact With?

For CBD users taking prescription medications, it’s necessary to consider whether CBD use will interfere with the drugs you’re taking.

Some interactions can be handled by modifying dosage or by staggering when CBD and the drugs in question are taken. However, only a physician can help you determine how best to incorporate CBD into your treatment plan.

Nonetheless, identifying which medications may interact with CBD is a necessary first step. Luckily, a growing body of research has emerged to assist with this vital step.

Researchers at Penn State developed a list of 139 medications that may be affected by the use of cannabinoids like CBD.

Most such drugs were mildly affected, however, and the researchers narrowed their focus to 57 medications for which cannabinoid use could cause serious complications.

Be sure to check the above list for your medication. For convenience, however, some of the most common such drugs include:

  • Warfarin, a blood thinner.
  • Amiodarone, a heart rhythm medication.
  • Levothyroxine, a thyroid medication.
  • Clobazam, lamotrigine, and valproate, and other medications for seizures.

If you are taking these or another medication on the list of 57 medications seriously impacted by cannabinoids, it is vitally important to discuss your CBD use with a trained physician.

How Does CBD Interfere With Medications?

When you take a medication, your body needs to process, or “metabolize”, it before it takes effect.

The body metabolizes drugs not only in the stomach but also in the liver.

The process is largely carried about by an important enzyme called cytochrome P450 (CYP450). CYP450 converts foreign substances, such as the drugs that you take, so that they can more easily be broken down by the body.

When multiple substances are taken alongside one another, they can “compete” for available CYP450. This slows the metabolization rate, which can interfere with the effectiveness of all such substances.

CBD, like many drugs, is broken down by enzymes in the CYP450 family. As such, CBD can interfere with the body’s ability to break down and eliminate other drugs that you may be taking.

When substances compete for CYP450, several things occur. The substances will not be broken down as rapidly, which may prevent them from taking full effect. Additionally, the substances will linger for longer in the body, which makes it more difficult to accurately administer subsequent doses.

This sort of drug interaction will seriously interfere with the efficacy of affected drugs. As such, it’s vitally important to understand whether CBD will interact with any of your prescription or OTC medications.

Doubling Up On Potential Side Effects

Even if CBD doesn’t interfere with your prescription medications, there is potential for increasing your drugs’ side effects.

CBD users don’t typically experience any adverse side effects from CBD on its own. Some users do experience mild side effects, however, especially when taking large doses. These symptoms can include:

  • Dry Mouth
  • Low Blood Pressure
  • Lightheadedness
  • Tiredness

If you take CBD alongside medications with similar side effects, it may increase the likelihood of experiencing these symptoms.

Some common drugs with similar potential side effects include:

  • Opioids
  • Benzodiazepines
  • Antipsychotics
  • Antidepressants
  • Antihistamines
  • Alcohol

Even if your medications don’t directly interact with CBD, it’s important to consider how their potential side effects might interact. Always avoid driving or operating heavy machinery when beginning a new combination of CBD and prescription or OTC medications.


And when in doubt, it always helps to talk to your doctor about your CBD use.