ZocdocAnswersWhy should you not take some medication with beverages such as grapefruit or cranberry juice?

Question

Why should you not take some medication with beverages such as grapefruit or cranberry juice?

I was taking a medication a few months ago and i noticed that I could not take grapefruit juice with that med. I was talking my a few of my friends and one of them said that she couldn't take cranberry juice with a medication that she had taken before. Why?

Answer

Grapefruit juice is notorious for interacting with various medications because of how it affects the liver's ability to do its job. One of the main jobs of the liver is to detox the rest of the blood, and some of the enzymes that are present to help it do that function are inactivated or have reduced activity in the presence of grapefruit juice. Other foods and vegetables will also have other side effects with some medications because of the fact that medications exist in a balance in your blood between being bound to other chemicals that are present in your blood and the free form of the drug. Usually, the free form of the drug is the form that is active, while the bound form is inactive. Removing or increasing the chemical or compound that binds to the drug will thus affect the active concentration of the drug. Still other foods can affect the effectiveness of drugs by altering the absorption of these drugs. Some of this has to do with the acidity of the food or drink, and other times it is by the mass effect of the food bolus carrying away the medication before it can be absorbed. Please discuss any particular drug questions or concerns with the prescribing provider.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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