Grapefruit dramatically increases drug levels
Grapefruit inhibits CYP3A4 enzyme in gut, preventing first-pass metabolism. Can increase blood levels of felodipine by 300%, amlodipine by 50%. Risk of severe hypotension, edema, and arrhythmias. Effect lasts 24+ hours.
Avoid grapefruit and grapefruit juice with CCBs. One glass can cause interaction.
Avoid entirely - timing separation doesn't help
Grapefruit dramatically increases drug levels. Avoid grapefruit and grapefruit juice with CCBs. One glass can cause interaction.
Avoid entirely - timing separation doesn't help
This interaction is rated “Warning” by Formulate. Grapefruit inhibits CYP3A4 enzyme in gut, preventing first-pass metabolism. Can increase blood levels of felodipine by 300%, amlodipine by 50%. Risk of severe hypotension, edema, and arrhythmias. Effect lasts 24+ hours.
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