Grapefruit juice interaction reports

Grapefruit Juice Interaction Reports from FDA s Postmarketing AERS... 

Information in the PI is typically based on the studies submitted by a drug s manufacturer. The FDA has also utilized spontaneous adverse event case reports as a tool in the evaluation of drug-grapefruit juice interaction labeling. Other sources of data that contribute to labeled information include studies or case reports from the medical literature. 

To identify case reports containing information on drug and grapefruit juice interaction, the Adverse Event Reporting System (AERS) (2) database... 

Anonymous. Grapefruit juice. Specific report of drug interactions. WHO Pharmaceuticals Newslett 2003 1 5. 

Lovastatin (Mevacor/ Altocor) [Antilipemic/HMG-CoA Reductase Inhibitor] Uses Hypercholesterolemia Action HMG-CoA reductase inhibitor Dose 20 mg/d PO w/ PM meal may T at 4-wk intervals to 80 mg/d max or 60 mg ER tab take w/ meals Caution [X, -] Avoid w/ grapefruit juice, gemfibrozil. Contra Active liver Dz Disp Tabs SE HA GI intolerance common promptly report any unexplained muscle pain, tenderness, or weakness (myopathy) Interactions T Effects W/ grapefruit juice T risk of severe myopathy W/ azole antifungals, cyclosporine, erythromycin, gemfibrozil, HMG-CoA inhibitors, niacin T effects OF warfarin >1 effects W/ isradipine, pectin EMS t Risk of photosensitivity Rxns T effects of warfarin concurrent EtOH use t risk of liver tox diltiazem and verapamil can T risk of lovastatin tox OD Unlikely to cause life-threatening Sxs... 

Huang SM, Hall SD, Watkins P, et al. Drug interactions with herbal products and grapefruit juice a conference report. Clin Pharmacol Ther 2004 75(1) 1-12. 

In addition to CYP3A4, enterocyte efflux transport proteins such as P-gp, and enterocyte uptake proteins, such as OATPs also appear to be involved in grapefruit rug interactions (24,72). The activity of P-gp has been reported to be altered by GFJ and orange juice in in vitro experiments (73,74), whereas the clinical relevance currently seems unclear, as demonstrated by inconsistent results from human clinical trials (22,75 77). 

Huang, S., Hall, S., Watkins, P., Love, L., Serabjit-Singh, C., Betz, J., Hoffman, F., Honig, P., Coates, P., Bull, J., Chen, S., Kearns, G., and Murray, M. 2004. Drug interactions with herbal products and grapefruit juice A conference report. Cliln. Pharmacol. Ther. 75, 1-12. 

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