Medication Interactions

When you take a medication, your body has to metabolize it (or break it down). Drug metabolism happens throughout the body, such as in the gut, but the liver does a big part of the job, too. A family of enzymes called cytochrome P450 (CYP450) does the important work of converting foreign substances so they can easily be eliminated from the body. Some medications or substances affect CYP450, either by slowing down or speeding up drug metabolism. That change in metabolism rate can alter how your body processes the medications or supplements you take, causing a drug interaction.

Cannabis, particularly THC and CBD, can interact with medications, potentially altering their effectiveness or increasing the risk of side effects. Cannabinoids like THC and CBD are metabolized by the same enzymes in the liver that process many prescription drugs. Cannabis may also amplify the effects of certain medications, especially those that affect the central nervous system (CNS). 

According to Drugs.com’s Cannabis Interactions research, there are currently around 400 medications known to interact with cannabis. These classifications are only a guideline. The relevance of a particular drug interaction to a specific individual is difficult to determine. Always consult your healthcare provider before starting or stopping any medication.

For the complete list of medications that have a potential interaction with cannabis, please click the link below.

https://www.drugs.com/drug-interactions/cannabis-index.html

Always Look for the Grapefruit Warning

Although studies are ongoing to determine potential interactions between CBD and specific medications, there’s one rule of thumb that can help consumers in the meantime: Avoid CBD if your medications have a grapefruit warning on the label. This warning indicates that people taking the medication should avoid consuming grapefruit or grapefruit juice.

According to the Food and Drug Administration, consuming grapefruit while on medication containing a grapefruit warning can lead to a higher concentration of the medication in the bloodstream and adverse side effects or even an overdose. More than 85 drugs interact with grapefruit and some closely related citrus juices — like Seville oranges, pomelos, and tangelos. That’s because chemicals in grapefruit known as furanocoumarins inhibit CYP3A4, in a similar fashion as CBD. The result is a slowed metabolization of medications.

Grapefruit warnings are common in several types of medications, but not all medications within a category will require the avoidance of grapefruit. Check your medication’s insert information or ask your doctor.