Drug absorption grapefruit juice effect

Tobacco and rifampin both induce hepatic enzymes, which may decrease the duration of action of the BZs. Grapefruit juice has received recent recognition as a factor in the pharmacokinetics of many drugs. Grapefruit juice slows down the GI absorption of midazolam and also decreases biotransformation, which leads to a delayed onset of effect and an increase in drowsiness (Ameer and Weintraub, 1997). 

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