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Using Medications Safely: Interactions Between Grapefruit Juice and Prescription Drugs1
R. Elaine Turner and Gail C. Rampersaud2How can Foods Interact with Drugs?
Foods can affect the way our bodies use medicines. The most common effect is for foods to reduce the amount of the drug that our body absorbs. This can make the drug less effective. For example, milk can reduce the absorption of tetracycline antibiotics.Foods can also increase absorption of a drug, and can affect how quickly or slowly a drug is eliminated from the body.
How does Grapefruit Juice affect Medications?
Grapefruit juice increases the absorption of some medicines. While absorbing more of a drug sounds like a good thing, it isn't. If more medication is absorbed than expected, the drug will have an increased effect. For example, a drug to help reduce blood pressure might lower blood pressure too far. Having more of a drug absorbed also increases the risk for side effects.What Types of Medicines Interact with Grapefruit Juice?
The good news is that most medicines do not interact with grapefruit juice. Interactions have been found between grapefruit juice and the some of the drugs in the following categories:
The generic and brand names of drugs that interact with grapefruit juice are listed on the following table.
- drugs used to treat high blood pressure
- "statin" drugs used to reduce blood cholesterol
- immunosuppressant drugs used after transplant operations
- protease inhibitors used to treat HIV/AIDS
- some anti-anxiety and antihistamine medications.
Drugs that Interact with Grapefruit Juice
Generic name
Trade name(s)
Drugs for high blood pressure
felodipine
Plendil®
nifedipine
Procardia®, Adalat®
nimodipine
Nimotop®
nisoldipine
Sular®
nicardipine
Cardene®
isradipine
DynaCirc®
Immunosuppressant Drugs
cyclosporine
Neoral®, Sandimmune®, SangCya®
tacrolimus
Prograf®
Drugs for High Cholesterol
atorvastatin
Lipitor®
lovastatin
Mevacor®
simvastatin
Zocor®
Drugs for Anxiety, Insomnia, or Depression
buspirone
BuSpar®
diazepam
Valium®
midazolam
Versed®
triazolam
Halcion®
zaleplon
Sonata®
carbamazepine
Tegretol®
clomipramine
Anafranil®
trazodone
Desyrel®
Antihistamine Drugs
astemizole
Hismanal®
Protease Inhibitors
saquinavir
Fortavase®, Invirase®
Should I Stop Drinking Grapefruit Juice?
You should first check with your physician or pharmacist to see if one of your medicines is affected by grapefruit juice. If so, your doctor may prescribe a different drug that doesn't interact with grapefruit juice.If you have been taking one of the medicines listed in the table, and you drink grapefruit juice, talk with your doctor before making any changes.
If your medicine is not affected by grapefruit juice, there is no reason to remove it from your diet. Grapefruit juice is an excellent source of vitamin C and contains other compounds like potassium that may help improve heart health.
What about Other Citrus Juices?
Juices from oranges or other citrus fruits do not interact with medications in the same way. Citrus fruits are good sources of many nutrients, and should be included regularly in a healthy diet.Where can I get more Information?
Talk to your pharmacist and physician about other interactions between foods and drugs. Keep in mind that herbal supplements can also interact with drugs! Check with your physician before taking any type of supplement. The Family and Consumer Sciences (FCS) agent at your county Extension office may have more written information and nutrition classes for you to attend. Also, a registered dietitian (RD) can provide you with reliable information.
Footnotes
1. This document is FSHN02-5, one of a series of the Food Science and Human Nutrition Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Original publication date February 6, 2002. Reviewed May 2003. Visit the EDIS Web Site at http://edis.ifas.ufl.edu.2. R. Elaine Turner, PhD, RD, assistant professor, and Gail C. Rampersaud, assistant in research and education, Department of Food Science and Human Nutrition, Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida, Gainesville, FL 32611. Reviewed by Linda B. Bobroff, PhD, RD, LD/N, Gail P.A. Kauwell, PhD, RD, LD/N, and Paul Doering, MS, University of Florida.
The Institute of Food and Agricultural Sciences (IFAS) is an Equal Opportunity Institution authorized to provide research, educational information and other services only to individuals and institutions that function with non-discrimination with respect to race, creed, color, religion, age, disability, sex, sexual orientation, marital status, national origin, political opinions or affiliations. For more information on obtaining other extension publications, contact your county Cooperative Extension service.
U.S. Department of Agriculture, Cooperative Extension Service, University of Florida, IFAS, Florida A. & M. University Cooperative Extension Program, and Boards of County Commissioners Cooperating. Larry Arrington, Dean.
Copyright Information
This document is copyrighted by the University of Florida, Institute of Food and Agricultural Sciences (UF/IFAS) for the people of the State of Florida. UF/IFAS retains all rights under all conventions, but permits free reproduction by all agents and offices of the Cooperative Extension Service and the people of the State of Florida. Permission is granted to others to use these materials in part or in full for educational purposes, provided that full credit is given to the UF/IFAS, citing the publication, its source, and date of publication.