Supplement × Prescription·Evidence index
PubMed indexes 8 records that name Grapefruit Juice and Simvastatin together, either in the title or in an interaction, co-administration, or pharmacokinetic context. Each one is listed below with its study design and, where the abstract states one, the authors’ own conclusion, quoted and linked. This page reports that literature. It does not tell you whether to combine them.
Every statement below is attributed to a named, dated, linked source.
This page lists published research relevant to Grapefruit Juice and Simvastatin. It deliberately does not state whether the combination is safe, whether it interacts, in which direction, at what dose, or how far apart to take them.
Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.
“Even one glass of grapefruit juice, taken daily, considerably increases the plasma concentrations of simvastatin and simvastatin acid. Grapefruit juice may increase both the cholesterol-lowering effect and the risk of adverse effects of simvastatin.”
Names both Grapefruit Juice and Simvastatin in its title.
Names both Grapefruit Juice and Simvastatin in its title.
“When simvastatin is taken 24 hours after ingestion of "high-dose" grapefruit juice, the effect of grapefruit juice on the AUC of simvastatin is only about 10% of the effect observed during concomitant intake of grapefruit juice and simvastatin. The interaction potential of even high amounts of grapefruit juice with CYP3A4 substrates dissipates within 3 to 7 days after ingestion of the last dose of grapefruit juice.”
Names both Grapefruit Juice and Simvastatin in its title.
“Grapefruit juice greatly increased serum concentrations of simvastatin and simvastatin acid and, to a lesser extent, those of active and total HMG-CoA reductase inhibitors. The probable mechanism of this interaction was inhibition of CYP3A4-mediated first-pass metabolism of simvastatin by grapefruit juice in the small intestine.”
Names both Grapefruit Juice and Simvastatin in its title.
“Interestingly, treatment with RS- or DS-GFJ alone significantly decreased plasma cholesterol levels by 22 % and 30 %, respectively. In conclusion, our results suggest that toxic effects in rats of concomitant intake of simvastatin and GFJ over 28 days are not more pronounced than those of simvastatin alone and that dose relationships between the administration of the juice and the drug may be important in determining the magnitude of the interaction.”
Names both Grapefruit Juice and Simvastatin in its title.
Names Grapefruit Juice and Simvastatin together in an interaction, co-administration, or pharmacokinetic context.
“Grapefruit juice significantly increased serum concentrations of atorvastatin acid, atorvastatin lactone, and active and total HMG-CoA reductase inhibitors, probably by decreasing CYP3A4-mediated first-pass metabolism of atorvastatin in the small intestine. On the other hand, grapefruit juice had no effect on the pharmacokinetics of pravastatin.”
Names Grapefruit Juice and Simvastatin together in an interaction, co-administration, or pharmacokinetic context.
“Grapefruit juice can greatly increase serum concentrations of lovastatin and its active metabolite, lovastatin acid, probably by preventing CYP3A4-mediated first-pass metabolism in the small intestine. The concomitant use of grapefruit juice with lovastatin and simvastatin should be avoided, or the dose of these 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors should be reduced accordingly.”
Names Grapefruit Juice and Simvastatin together in an interaction, co-administration, or pharmacokinetic context.
Search-based evidence indexes have real limits, and it is worth being explicit about them:
NutriStack is a free iPhone app for organising a supplement routine: what you take, when, and what the published record says about it. Its exploratory interaction checker covers Grapefruit Juice, Simvastatin, and several hundred other substances.
The checker is a research and organisation tool, not a clinical decision aid, and its per-pair assessments are excluded from search until they pass claim-level review.
NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.
