Grapefruit Juice and Medication Interactions (cont.)

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Research about the interaction of grapefruit juice with drugs suggests that compounds in grapefruit juice, called furanocoumarins (for example, bergamottin), may be responsible for the effects of grapefruit juice. Researchers believe that furanocoumarins block the enzymes in the intestines that normally break down many drugs. One glass of grapefruit juice could elicit the maximum blocking effect, and the effect may persist for longer than 24 hours. Since the effects can last for such a prolonged period of time, grapefruit juice does not have to be taken at the same time as the medication in order for the interaction to occur. Therefore, unlike similar interactions, where the interaction can be avoided by separating the administration of the two interacting agents by a couple of hours, administration of grapefruit juice with susceptible drugs should be separated by 24 or more hours to avoid the interaction. Since this is not practical for individuals who are taking a medication daily, they should not consume grapefruit juice when taking medications that are affected by grapefruit juice.

The grapefruit juice-drug interaction can lead to unpredictable and hazardous levels of certain important drugs.

These are medications with which grapefruit juice should NOT be consumed unless advised by a doctor:

Medically Reviewed by a Doctor on 7/3/2014