But it isn’t good for you when it affects the way your medicines work. Grapefruit juice and fresh grapefruit can interfere with the action of some prescription drugs, as well as a few nonprescription drugs.

This interaction can be dangerous, says Shiew Mei Huang, Ph.D., acting director of the Food and Drug Administration’s Office of Clinical Pharmacology. With most drugs that interact with grapefruit juice, “the juice increases the absorption of the drug into the bloodstream,” she said. “When there is a higher concentration of a drug, you tend to have more adverse events.”

For example, if you drink a lot of grapefruit juice while taking certain statin drugs to lower cholesterol, too much of the drug may stay in your body, increasing your risk for liver damage and muscle breakdown that can lead to kidney failure.

Drinking grapefruit juice several hours before or several hours after you take your medicine may still be dangerous, said Dr. Huang, so it’s best to avoid or limit consuming grapefruit juice or fresh grapefruit when taking certain drugs.

Examples of some types of drugs that grapefruit juice can interact with are:

  • some statin drugs to lower cholesterol, such as Zocor (simvastatin), Lipitor (atorvastatin) and Pravachol (pravastatin);
  • some blood pressure-lowering drugs, such as Nifediac and Afeditab (both nifedipine);
  • some organ transplant rejection drugs, such as Sandimmune and Neoral (both cyclosporine);
  • some anti-anxiety drugs, such as BuSpar (buspirone);
  • some anti-arrhythmia drugs, such as Cordarone and Nexterone (both amiodarone);
  • some antihistamines, such as Allegra (fexofenadine).

Tips for avoiding drug/grapefruit juice interactions:

  • Ask your pharmacist or other heath care professional if you can have fresh grapefruit or grapefruit juice while using your medication
  • Read the medication guide or patient information sheet that comes with your prescription medicine to find out if it could interact with grapefruit juice
  • Read the drug facts label on your nonprescription medicine, which will let you know if you shouldn't have grapefruit or other fruit juices with it
  • If you must avoid grapefruit juice with your medicine, check the label of bottles of fruit juice or drinks flavored with fruit juice to make sure they don't contain grapefruit juice
  • Seville oranges (often used to make orange marmalade) and tangelos (a cross between tangerines and grapefruit) affect the same enzyme as grapefruit juice, so avoid these fruits as well if your medicine interacts with grapefruit juice

Grapefruit juice does not affect all the drugs in the categories above. Ask your pharmacist or other health care professional to find out if your specific drug is affected.

The FDA has required some prescription drugs to carry labels that warn against consuming grapefruit juice or fresh grapefruit while using the drug, says Dr. Huang. And the agency’s current research into drug and grapefruit juice interaction may result in label changes for other drugs as well.

Dr. Kim Dr. Kim

Dr. Kim Okamura

I'm Dr. Kim Okamura and this blog is a product of my love of dentistry. I dedicate it to all the patients I have served so that they may better understand my craft. The information here will give you and others the power to maintain and protect one of your most priceless gifts ... your SMILE.