Can Grapefruit Juice Interfere With My Medications?

We’re not talking about rare drugs either: The medications to watch out for include common blood pressure drugs, erectile dysfunction medications, anti-infections drugs, antihistamines, steroids, opioid painkillers, and even birth control pills.

Here is a list of some common medications affected by grapefruit juice:

  • Some cholesterol-lowering medications: simvastatin (Zocor), atorvastatin (Lipitor), lovastatin (Mevacor)
  • Many blood pressure medications: nifedipine (Procardia, Adalat CC), amlodipine (Norvasc), felodipine (Plendil)—to name a few
  • Some anti-arrhythmia medications: verapamil (Calan), amiodarone (Cordarone)
  • Blood thinners: Eliquis, Xarelto, clopidogrel (Plavix)
  • Some erectile dysfunction medications: sildenafil (Viagra), tadalafil (Cialis), vardenafil (Levitra)
  • Some anti-anxiety medications: sertraline (Zoloft), buspirone (Buspar), alprazolam (Xanax), diazepam (Valium)
  • Some opioid painkillers: oxycodone (Roxicodone, Oxycontin), methadone (Dolophine), fentanyl (Duragesic)
  • Drugs with estrogen hormones: estradiol (Estrace) and estrogen-containing contraception, such as Loestrin, Yasmin, and Aviane (your birth control will still work, but you might get more side effects)
  • Erythromycin (Ery) (Clarithromycin is ok)
  • Some HIV medications: Intelence, Invirase
  • Fexofenadine (Allegra)
  • Some steroids: budesonide (Pulmicort), methylprednisone (Medrol)
  • Montelukast (Singulair)

A more complete list is available here, but the list of affected medications is always changing so it’s best to check with your doctor or pharmacist if you are a grapefruit-lover.

If you really want to know…

Why does grapefruit interact with certain medications?

Grapefruit juice blocks enzymes responsible for breaking down medications in the body. The main enzyme affected is one called cytochrome p450 (or CYP450, for short). This can make the medication last longer in the blood and cause unwanted side effects.

Grapefruit can also interfere with medications in other ways: Sometimes it stops the medication from being converted in the body into a more “active” form. This can make the medication less effective.  

Either way, grapefruit only has an effect on medications that you take as pills. It doesn’t affect intravenous medications.

How does this affect me?

This is where it gets complicated. The effect of mixing medications with grapefruit juice depends on so many factors—like which medications you take and how much grapefruit you consume—that we can’t give you a straight-up answer. That said, we’ll take a look at some common scenarios below.

Some meds can be taken carefully with grapefruit juice


Sildenafil (Viagra)

Some medications are less effective when taken with grapefruit juice

Fexofenadine (Allegra)

Clopidogrel (Plavix)

Levothyroxine (Synthroid)

Tamoxifen (Nolvadex)

Some medications can reach toxic levels when taken with grapefruit juice

Some medications can reach toxic levels if taken with grapefruit juice. Taking a chance with these is not worth it, as the risks can be potentially serious. If you are on the following medications, you should change your morning drink or cocktail mixer to something other than grapefruit juice.

Blood pressure drugs


Blood thinners

Anti-anxiety medications

Opioid painkillers



But I LOVE grapefruit juice…

Unfortunately, even a glass of the tart tangy nectar is enough to have a significant and lasting effect on the way your body handles your medication (anywhere from a few hours to a few days).

So, if you are a committed grapefruit-lover, we recommend talking to your doctor about your medications and how they might interact with grapefruit. You might be able to change to another medication that is not affected by grapefruit. Or you might have to switch allegiance to orange, apple, or pomegranate juice instead.

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