Impact of Grapefruit Juice on the Antiplatelet Activity of Loading and Maintenance Doses of Clopidogrel in Healthy Volunteers
نویسندگان
چکیده
BACKGROUND Grapefruit juice impacts the metabolism of a number of drugs via inhibition of a variety of metabolic enzymes. This study evaluated the impact of grapefruit juice on the antiplatelet activity of a loading dose and 7 days of maintenance therapy with clopidogrel. METHODS Healthy volunteers participated in two separate treatment protocols. The first protocol included a single 300 mg loading dose of clopidogrel and the second protocol included maintenance therapy with clopidogrel 75 mg given for 7 consecutive days. In both protocols, subjects were randomized to take clopidogrel with grapefruit juice or with tap water. At 6 h after the loading dose and at 6 h after the last maintenance dose of clopidogrel, a P2Y12 reaction unit (PRU) value using the VerifyNow® P2Y12 assay was determined. A PRU value > 235 was defined as high on-treatment platelet reactivity (defined as clopidogrel hyporesponse). RESULTS Fourteen subjects completed the loading dose protocol while 17 subjects completed the maintenance dose protocol. Following administration of the loading dose, the mean PRUs with grapefruit juice and tap water were 235.2 (95% confidence interval (CI): 210.4-260.0) and 177.4 (95% CI: 141.6-213.2), respectively (P = 0.001). Following administration of the loading dose, the numbers of subjects with a PRU > 235 with grapefruit juice and tap water were 9 (64%) and 3 (21%), respectively (P = 0.05). In the maintenance dose protocol, the mean PRUs with grapefruit juice and tap water were 212.4 (95% CI: 175.8-249.0) and 186.1 (95% CI: 149.6-222.7), respectively (P = 0.059). In the maintenance dose protocol, the proportions of patients with a PRU > 235 with grapefruit juice and tap water were 9 (53%) and 4 (23%), respectively (P = 0.16). DISCUSSION Compared to tap water, grapefruit juice significantly increased the mean PRU in patients following a 300 mg loading dose of clopidogrel. The increase in mean PRU after 7 days of a 75 mg/day maintenance dose of clopidogrel was also increased by grapefruit juice, but the magnitude of the increase was not statistically significant. The proportion of subjects with high on-treatment platelet reactivity with clopidogrel after ingestion with grapefruit juice was not significant during either the loading or maintenance dose. The results of our study are insufficient to reach a valid conclusion concerning an interaction between clopidogrel and grapefruit juice.
منابع مشابه
Influence of methadone on clopidogrel in addicts on methadone maintenance therapy
Background: Clopidogrel is a prodrug that converts in the liver to an active thiol metabolite, which irreversibly inhibits the platelet P2Y12 adenosine diphosphate receptor. It seems that methadone as CYP2C19 inhibitor affects ticlopidine activity in vivo. This study aimed to test the ability of methadone in changing ticlopidine pharmacokinetics. Methods: We conducted a case–control st...
متن کاملComparison of antiplatelet activity of garlic tablets with cardio-protective dose of aspirin in healthy volunteers: a randomized clinical trial
Objective: Some of the adverse effects of aspirin including peptic ulcers, gastrointestinal bleeding and aspirin resistance compelled researchers to find a suitable alternative with fewer adverse effects. In this clinical trial, we aimed to find the effective antiplatelet dose of garlic. Materials and Methods: This randomized controlled clinical trial (RCT) was conducted on 62 healthy volunteer...
متن کاملEffect of Honey on CYP3A4 Enzyme and P-Glycoprotein Activity in Healthy Human Volunteers
The activity of cytochrome p450 isozyme 3A4 (CYP3A4) enzyme and P-glycoprotein (P-gp) is modulated by grapefruit juice and herbal drugs. CYP3A4 is the major phase I drug metabolizing enzyme and P-gp is an ATP-dependent drug efflux pump that regulates the intestinal absorption of orally administered drugs. Honey is commonly consumed as a dietary supplement. However, its influence on human CY...
متن کاملAssociation of ABCB1 Gene Polymorphisms and Clopidogrel Responsiveness in Iranian Patients undergoing Percutaneous Coronary Intervention
Clopidogrel is an antiplatelet agent currently used for preventing stent thrombosis. Despite certain clinical benefits of clopidogrel in patients undergoing percutaneous coronary intervention (PCI), adequate antiplatelet effect has not been obtained in some patients. The present study was designed to investigate the potential association of ABCB1 (ATP-Binding Cassette, Subfamily B, member1) gen...
متن کاملAssociation of ABCB1 Gene Polymorphisms and Clopidogrel Responsiveness in Iranian Patients undergoing Percutaneous Coronary Intervention
Clopidogrel is an antiplatelet agent currently used for preventing stent thrombosis. Despite certain clinical benefits of clopidogrel in patients undergoing percutaneous coronary intervention (PCI), adequate antiplatelet effect has not been obtained in some patients. The present study was designed to investigate the potential association of ABCB1 (ATP-Binding Cassette, Subfamily B, member1) gen...
متن کامل