- With Mayo Clinic nutritionist
Katherine Zeratsky, R.D., L.D.read biographyclose window
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.
Consumer health basics (5)
- Osteopathic medicine: What kind of doctor is a D.O.?
- What is compassionate use of experimental drugs?
- After a flood, are food and medicine safe to use?
- see all in Consumer health basics
Alternative medicine (28)
- Kombucha tea: Does it have health benefits?
- Do infrared saunas have any health benefits?
- Aromatherapy: Is it worthwhile?
- see all in Alternative medicine
- Antibiotics and alcohol: Should I avoid mixing them?
- Grapefruit juice: Beware of dangerous medication interactions
- Bioidentical hormones: Are they safer?
- see all in Medications
Grapefruit juice: Beware of dangerous medication interactions
I like to drink grapefruit juice but hear that it can interfere with some prescription medications. Is that true?
from Katherine Zeratsky, R.D., L.D.
Yes. Grapefruit and certain other citrus fruits and products can interfere with several kinds of prescription medications.
Don't take these interactions lightly. Some can cause potentially dangerous health problems. Check with your doctor or pharmacist before consuming any grapefruit or other citrus products 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.
Problems arise because chemicals in the fruit can interfere with the enzymes that break down (metabolize) the medication in your digestive system. As a result, the medication may stay in your body for too short or too long a time. A medication that's broken down too quickly won't have time to work. On the other hand, a medication that stays in the body too long can increase to potentially dangerous levels, causing serious side effects.
The list of medications that can interact with grapefruit is long and includes commonly prescribed medicines that fight infections, reduce cholesterol, treat high blood pressure and treat heart problems. In addition, researchers are identifying other foods, including other fruits, that may interact with medications.
Play it safe with prescription drugs. Always ask your doctor or pharmacist when you get a new prescription if it interacts with any foods (or other medicines). If the answer is yes, ask whether you need to eliminate that food from your diet.Next question
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 Jan. 10, 2013.
- Dolton MJ, et al. Fruit juices as perpetrators of drug interactions: The role of organic anion-transporting polypeptides. Clinical Pharmacology & Therapeutics. 2012;92:622.
- Bailey DG, et al. Grapefruit-medication interactions: Forbidden fruit or avoidable consequences? CMAJ. In Press. Accessed Jan. 10, 2013.
- Sheps SG (expert opinion). Mayo Clinic, Rochester, Minn. Jan. 10, 2013.