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Why can't you drink grapefruit juice if you take certain medications?

Did you know that grapefruit juice can interact with certain medications such as Valium, BusPar and Zoloft, as well as medications to reduce cholesterol and high blood pressure? This interaction happens in the intestines which is where many enzymes such as CYP3A do their work in the body. The role of CYP3A is to regulate the absorption of food and other substances in the blood, but it also prevents a portion of certain medications from being absorbed by partially destroying them. This is a normal event in the digestive system and is taken into account in the dosages of medication.

Grapefruit juice contains natural chemicals such as furanocoumarines that inhibit the action of CYP3A which will increase the concentration of certain medications in the bloodstream. It may seem as though this would be a great way to make our medication work better, however the reality is that an uncontrolled increase of the medication in the blood can increase its secondary effects and actually become very dangerous!
Thus, if you like to drink grapefruit juice in the morning and are also taking a medication that may interact with it, talk about it to your doctor! You can also change your habits by switching to orange juice or by asking your doctor if there is an equivalent medication that does not interact with grapefruit juice. For those of you who think you could not live without grapefruit juice, just be patient because many researchers are working on commercialising grapefruit juices without furanocoumarines!
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