title: Medicinal importance of grapefruit juice and its interaction with various drugs.
abstract: Grapefruit juice is consumed widely in today's health conscious world as a protector against cardiovascular diseases and cancers. It has however, been found to be an inhibitor of the intestinal cytochrome P - 450 3A4 system, which is responsible for the first pass metabolism of many drugs. The P - glycoprotein pump, found in the brush border of the intestinal wall which transports many of these cytochrome P - 450 3A4 substrates, has also been implicated to be inhibited by grapefruit juice. By inhibiting these enzyme systems, grapefruit juice alters the pharmacokinetics of a variety of medications, leading to elevation of their serum concentrations. Most notable are its effects on the calcium channel antagonist and the statin group of drugs. In the case of many drugs, the increased serum concentration has been found to be associated with increased frequency of dose dependent adverse effects. In this review, we have discussed the phytochemistry of grapefruit juice, the various drugs involved in the drug - grapefruit juice reaction with their mechanisms of action and have presented the clinical implications of these interactions.
authors.affiliation: Medical College, Aga Khan University, Stadium Road, Karachi, Pakistan. jawad.kiani@gmail.com
authors.forename: Jawad
authors.initials: J
authors.lastname: Kiani
authors.forename: Sardar Z
authors.initials: SZ
authors.lastname: Imam
mesh_terms: D001628:Beverages / Q000009:adverse effects*; D001682:Biological Availability; D002121:Calcium Channel Blockers / Q000494:pharmacology; D032083:Citrus paradisi / Q000737:chemistry*; D051544:Cytochrome P-450 CYP3A; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism; D018565:Food-Drug Interactions; D006801:Humans
chemical_list: D002121:Calcium Channel Blockers; D065607:Cytochrome P-450 Enzyme Inhibitors; D003577:Cytochrome P-450 Enzyme System; D051544:Cytochrome P-450 CYP3A; C510163:CYP3A4 protein, human