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Katherine Zeratsky, R.D., L.D.
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Katherine Zeratsky, R.D., L.D.
Katherine Zeratsky, R.D., L.D.
As a specialty editor for the nutrition and healthy eating guide, Katherine Zeratsky helps you sort through the facts and figures, the fads and the hype to learn more about nutrition and diet.
A Marinette, Wis., native, Katherine is certified in dietetics by the state of Minnesota and the American Dietetic Association. She has been with Mayo Clinic since 1999.
She is active in nutrition-related curriculum and course development in wellness nutrition at Mayo Clinic in Rochester, Minn., and nutrition education related to weight management and practical applications of nutrition-related lifestyle changes.
Other areas of interest include food and nutrition for all life stages, active lifestyles and the culinary arts.
She graduated from the University of Wisconsin-Madison, served a dietetic internship at the University of Iowa Hospitals and Clinics, and worked as a registered dietitian and health risk counselor at ThedaCare of Appleton, Wis., before joining the Mayo Clinic staff.
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Question
Grapefruit juice: Beware of dangerous medication interactions
I like to drink grapefruit juice but hear that it can interfere with some of my prescription medications. Is that true?
Answer
from Katherine Zeratsky, R.D., L.D.
Yes, grapefruit juice, other grapefruit products and certain other citrus fruits can interfere with several kinds of prescription medications. Don't take these interactions lightly, as some can cause potentially dangerous health problems. Check with your doctor or pharmacist before consuming any grapefruit products or citrus fruits if you take prescription medications. You may need to eliminate grapefruit products from your diet. Simply taking your medication and grapefruit product at different times doesn't stop the interaction.
Certain chemicals that grapefruit products and citrus fruits contain can interfere with the enzymes that break down (metabolize) various medications in your digestive system. As a result, more medication stays in your body. This can increase the potency of your medication to potentially dangerous levels, causing serious side effects.
Pomelos and Seville oranges, a type of bitter orange often used to make marmalades and compotes, may have a similar effect. Researchers are identifying other foods that also may interact with medications, so check with your doctor or pharmacist if you have any concerns.
Here are a few examples of prescription medications that can have serious interactions with grapefruit products. This is not a complete list of grapefruit-medication interactions, so check with your doctor or pharmacist to see if your medication is affected.
| Examples of grapefruit-medication interactions | |
|---|---|
| Type of medication | Medication name |
| Anti-anxiety | Buspirone |
| Anti-arrhythmia | Amiodarone (Cordarone) |
| Antidepressant | Sertraline (Zoloft) |
| Antihistamine | Fexofenadine (Allegra) |
| Anti-retroviral | Saquinavir (Invirase), indinavir (Crixivan) |
| Anti-seizure | Carbamazepine (Carbatrol, Tegretol) |
| Calcium channel blocker | Nifedipine (Procardia), nimodipine (Nimotop), nisoldipine (Sular) |
| Immunosuppressant | Cyclosporine (Neoral, Sandimmune), tacrolimus (Prograf), sirolimus (Rapamune) |
| Statin | Simvastatin (Zocor), lovastatin (Mevacor), atorvastatin (Lipitor) |
Bioidentical hormones: Are they safer?
- Kiani J, et al. Medicinal importance of grapefruit juice and its interaction with various drugs. Nutrition Journal. 2007;6:33.
- Grapefruit. Natural Medicines Comprehensive Database. http://www.naturaldatabase.com. Accessed Aug. 16, 2010.
- Sheps SG (expert opinion). Mayo Clinic, Rochester, Minn. Aug. 17, 2010.
- Buss Preszler LK (expert opinion). Mayo Clinic, Rochester, Minn. Aug. 19, 2010.
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