Grapefruit and Heart Medications

Disclaimer: Always consult your doctor or pharmacist regarding any concerns you may have about your medications or side effects. The article Grapefruit and Heart Medications is for educational purposes only, and is not a substitute for individualized and qualified medical advice.

Have you ever been told to avoid grapefruit or grapefruit juice when you started a new medication? Or maybe you've seen it on the bottle: a warning not to consume grapefruit while taking that med? And isn't grapefruit healthy?

While grapefruit is certainly healthy, and even good for your heart, it also adversely interacts with many heart medications. This can lead to blood pressure that's too low, medication toxicity, and (if untreated) potentially death. That's why it's so important to avoid grapefruit when you take certain heart medications. Which ones? Read on to find out which heart medications may interact with grapefruit!

Grapefruit and Cholesterol Medication

Grapefruit and grapefruit juice can interact with some cholesterol medications, most notably, statins. That's because these drugs metabolize in the gut, via a certain enzyme called CYP3A. Grapefruit contains compounds that inhibit this enzyme. That makes the drug more powerful than it is intended to be (1). In some cases it can even become toxic.

Not all statins use that same enzyme, though. There are three statins that are of concern here: simvastatin (Zocor), lovastatin (Mevacor), and atorvastatin (Lipitor) (2, 3, 4). If you are taking any of those three statins, make sure to discuss grapefruit consumption with your doctor. If you love it and consume it often, you may be able to switch to a different statin. 

The amount of grapefruit or grapefruit juice you may be able to consume without side effects varies, and it's not possible to predict whether you'll be able to tolerate more or less. That's why it's so important to discuss it with your prescribing physician. Many people will be able to consume half a grapefruit or a small glass of juice. It's generally considered "safer" to consume grapefruit in its whole fruit form, as the compound responsible for the interaction is more concentrated in juice (it would take several grapefruit squeezed to make a glass of juice).

Grapefruit and Blood Pressure Medication

The main group of blood pressure medications of concern related to grapefruit consumption is calcium channel blockers. Calcium channel blockers work by relaxing the muscles in the walls of your arteries, thereby lowering your blood pressure. These medications metabolize via the same CYP3A pathway as the statins above, meaning they are also prone to interacting with grapefruit (5). Consuming grapefruit with calcium channel blockers can increase the amount of the drug circulating in your body, leading to dangerously low blood pressure, or other side effects.

If you are taking any of the following calcium channel blockers (not all calcium channel blockers interact), be sure to talk with your doctor about grapefruit: felodipine (Plendil), nimodipine (Nymalize), or nisoldipine (Sular) (6, 7, 8). 

Also, even though it isn't a calcium channel blocker, take caution with eplerenone (Inspra), as grapefruit can cause similar side effects (9).

As with statins, the amount an individual may be able to consume safely is variable. Severe side effects were observed in some people with just one cup of whole grapefruit segments. If you have concerns about your grapefruit consumption and medication, talk with your doctor about an alternate medication.

Grapefruit and Blood Thinners

Let me start with the good news here: grapefruit does not affect warfarin (Coumadin). This is a popular medication. While vitamin K is a concern with warfarin, grapefruit is not. Aspirin is also not affected by grapefruit.

Some other blood thinners, however, may be affected by grapefruit consumption. I say they 'may be affected' because there aren't many formal studies that have been conducted on these newer medications with regard to how grapefruit may or may not impact them. However, they utilize that same CYP3A pathway in the gut as the previous medications, so it is prudent to moderate your consumption of grapefruit if you take any of these: ticagrelor (Brilinta), apixaban (Eliquis), or rivaroxaban (Xarelto) (10, 11, 12).

It is important to never stop taking your blood thinner without first speaking with your doctor! Doing so may cause blood clots to form, potentially resulting in stroke.

Grapefruit and grapefruit juice is implicated in over 85 medication interactions, so always check the label and package inserts on your medications. You can also speak with your doctor or pharmacist about any concerns you have about side effects or interactions. With a little investigation, you can be sure to avoid food-medication interactions and rest easy!