A client is prescribed a medication that requires the cytochrome P450 3A4 enzyme system for absorption. Because of this, what should the nurse instruct the client when taking this medication?

Question

Quizplus · Accepted Answer

Grapefruit juice inhibits the cytochrome P450 3A4 enzyme system responsible for "first-pass metabolism"of many drugs. The inhibition of the enzyme allows more drug to be absorbed than normally would occur, elevating plasma drug levels. The cytochrome P450 3A4 enzyme is not identified as being affected by the presence or absence of food.

A Client Is Prescribed a Medication That Requires the Cytochrome