Why You Can't Mix Grapefruit With Some Medications, According to MDs

There's something ultra-refreshing about cutting into a fresh, juicy grapefruit, but before you go to town, you need to check your medications. You may be thinking, "Huh?! Why does grapefruit interfere with medication?" Good thing you asked, because the citrus fruit can actually cause dangerous interactions with some meds.

"Grapefruit is a healthy food that is rich in nutrients; however, both grapefruit and grapefruit juice can interact with many medications and have some negative impacts," says Laura Purdy, MD, a board-certified family-medicine physician. "There are cells that line your small intestine and contain an enzyme that helps break down certain medications, and grapefruit also has some of these enzymes in the juice, which when consumed, creates more of the medication to enter your bloodstream," she explains. As a result, the buildup of medication can lead to undesirable, often dangerous, side effects, she says.

But which medications should not be taken with grapefruit? FYI: grapefruit and blood pressure medications and grapefruit and antidepressants are just two combinations that should be avoided without talking to your doctor. Keep scrolling for everything you need to know about grapefruit medication interactions and how to stay safe.

Grapefruit can interfere with medication because it contains compounds that inhibit an enzyme in the gastrointestinal tract called CYP3A4, says Shoshana Ungerleider, MD, a board-certified internal-medicine physician and founder of End Well Foundation. "This enzyme is responsible for metabolizing many drugs, and when grapefruit is consumed, it can increase the concentration of certain medications in the blood, potentially leading to adverse effects or toxicity," she explains.

To break this down a bit more, many drugs are metabolized with the help of CYP3A4 in the small intestine, per the US Food and Drug Administration (FDA). Grapefruit juice then blocks the action of the enzyme and gets in the way of metabolization, which leads to a buildup of medication in the bloodstream, Dr. Ungerleider says. "It's not typically a question of whether the medications will work, but rather that they may work too well, or unpredictably, which can be dangerous," she explains.

Always talk to your doctor, but according to the FDA, the following are common medications that should not be taken with grapefruit:

Just note this is not an extensive list nor are the medications you should avoid mixing with grapefruit limited to these examples, so it's essential to consult with a healthcare provider for specific guidance when taking prescription medication, Dr. Ungerleider notes.

Maybe. Since the range of grapefruit medication interactions is quite extensive, it's best to consult with a doctor about your specific medication and/or check the drug warning label and discuss with your pharmacist, Dr. Purdy says. "There are some cases where you should avoid grapefruit altogether, but it can vary because the enzyme in the intestine varies from person to person," she explains. It also depends on how much grapefruit you consume, your age, the type of medication, and the specific dosage, she adds.

That said, if you do eat grapefruit or drink grapefruit juice while taking "off-limit" medications, you may get sick because the medicine can stay in your body for too long or sometimes too short a time, Dr. Purdy says. "If the medicine stays in your blood for too long, it can build up to more concerning levels and cause side effects, but if the medicine breaks down too quickly, it won't have time to work," she explains. "If you love citrus, try swapping for lemons, limes, and most oranges, which are less likely to interact with medications."

If you take medication and recently had grapefruit, talk to your doctor if you experience muscle pain or swelling, drowsiness or dizziness, irregular heartbeat, nausea, headaches, or low blood pressure, Dr. Purdy says. You may also experience enhanced side effects of the medication due to increased levels in your system, which may or may not cause an immediate effect, so always consult with a healthcare provider for the safest course of action, Dr. Ungerleider says.

Before taking any new medications, talk to your doctor about potential interactions with grapefruit, and/or check the warning labels on your medication bottle before leaving the pharmacy, Dr. Purdy says. "Healthcare providers can give the best advice on whether any amount of grapefruit is safe and, if so, how much," Dr. Ungerleider adds.