avoid plavix plus nexium/prevacid

FDA: Avoid Coadministration of Clopidogrel and Omeprazole, Esomeprazole

SILVER SPRING, Md -- November 17, 2009 -- The US Food and Drug Administration (FDA) has new data showing that the proton pump inhibitor (PPI) omeprazole (Prilosec/Prilosec OTC) reduces the anti-blood clotting effect of clopidogrel (Plavix) by almost half when these 2 medicines are taken by the same patient. Patients at risk for heart attacks or strokes who use clopidogrel to prevent blood clots will not get the full effect of this medicine if they are also taking omeprazole; therefore, the FDA recommends that the coadministration of omeprazole and clopidogrel be avoided.

The new recommendations, updated from a January 2009 Early Communication, are based on study results from the manufacturers of clopidogrel. The studies confirm that coadministration of omeprazole with clopidogrel results in decreased levels of clopidogrel's active metabolite, reducing clopidogrel's anticlotting effect.

Omeprazole inhibits the drug-metabolising enzyme (CYP2C19), which is responsible for the conversion of clopidogrel into its active metabolite. The new studies compared the amount of clopidogrel's active metabolite in the blood and its effect on platelets in patients who took clopidogrel plus omeprazole versus those who took clopidogrel alone. A reduction in active metabolite levels of about 45% was found in those who received clopidogrel with omeprazole compared with those taking clopidogrel alone. The effect of clopidogrel on platelets was reduced by as much as 47% in patients receiving clopidogrel and omeprazole together. These reductions were seen whether the drugs were given at the same time or 12 hours apart.

Since the level of inhibition among other PPIs varies, it is unknown to what amount other PPIs may interfere with clopidogrel. However, esomeprazole (Nexium), a PPI that is a component of omeprazole, inhibits CYP2C19 and should also be avoided in combination with clopidogrel.

Other stomach acid-reducing drugs, such as ranitidine (Zantac), famotidine (Pepcid), nizatidine (Axid), or antacids, are not expected to interfere with the anticlotting activity of clopidogrel because they do not inhibit CYP2C19 activity. However, cimetidine (Tagamet/Tagamet HB) does inhibit CYP2C19 activity and should not be used.

In addition to cimetidine, other drugs that are potent inhibitors of the CYP2C19 enzyme would be expected to have a similar effect and should be avoided in combination with clopidogrel. These include fluconazole (Diflucan), ketoconazole (Nizoral), voriconazole (VFEND), etravirine (Intelence), felbamate (Felbatol), fluoxetine (Prozac, Sarafem, Symbyax), fluvoxamine (Luvox), and ticlopidine (Ticlid).

Sanofi-aventis and Bristol-Myers Squibb, the makers of Plavix (clopidogrel), are updating this drug's label with the details of the studies and are conducting follow-up studies to further explore drug interactions with clopidogrel.

Until further information is available, FDA recommends the following:
• The concomitant use of omeprazole and clopidogrel should be avoided because of the effect on clopidogrel's active metabolite levels and anticlotting activity. Patients at risk for heart attacks or strokes, who are given clopidogrel to prevent blood clots, may not get the full protective anticlotting effect if they also take prescription omeprazole or the OTC form.
• Separating the dose of clopidogrel and omeprazole in time will not reduce this drug interaction.
• Other drugs that should be avoided in combination with clopidogrel because they may have a similar interaction include esomeprazole, cimetidine, fluconazole, ketoconazole, voriconazole, etravirine, felbamate, fluoxetine, fluvoxamine, and ticlopidine.
• At this time the FDA does not have sufficient information about drug interactions between clopidogrel and PPIs other than omeprazole and esomeprazole to make specific recommendations about their coadministration. Healthcare professionals and patients should consider all treatment options carefully before beginning therapy.
• There is no evidence that other drugs that reduce stomach acid, such as most H2 blockers ranitidine (Zantac), famotidine (Pepcid), nizatidine (Axid), except cimetidine (Tagamet and Tagamet HB - a CYP2C19 inhibitor), or antacids interfere with the anticlotting activity of clopidogrel. Ranitidine and famotidine are available by prescription and OTC to relieve and prevent heartburn and antacids are available OTC to relieve heartburn.
• Talk with your patients about the OTC medicines they take. Be aware that patients may be taking nonprescription forms of omeprazole and cimetidine.

The FDA will continue to investigate other drug interactions with clopidogrel. The FDA plans on presenting this issue at the next meeting of the FDA's Drug Safety Oversight Board in November. The Agency will communicate any further recommendations or conclusions once additional information is available.

RELATED LINKS:
PPIs Thwart Clopidogrel's Anticlotting Effectiveness in Diabetics Post Stenting: Presented at ADA

Effectiveness of Clopidogrel May Be Reduced by Common Heartburn Drugs: Presented at SCAI

Certain PPIs Increase Risk of Heart Attacks for Patients on Clopidogrel

SOURCE: US Food and Drug Administration

erythropoietin and vasospasm after SAH- synergistic with statins

 J Neurosurg  

Interaction of neurovascular protection of erythropoietin with age, sepsis, and statin therapy following aneurysmal subarachnoid hemorrhage; Tseng MY, Hutchinson PJ, Kirkpatrick PJ; Journal of Neurosurgery (Nov 2009)

Object In a previous randomized controlled trial, the authors demonstrated that acute erythropoietin (EPO) therapy reduced severe vasospasm and delayed ischemic deficits (DIDs) following aneurysmal subarachnoid hemorrhage. In this study, the authors aimed to investigate the potential interaction of neurovascular protection by EPO with age, sepsis, and concurrent statin therapy. Methods The clinical events of 80 adults older than 18 years and with<72 hours of aneurysmal subarachnoid hemorrhage, who were randomized to receive 30,000 U of intravenous EPO-beta or placebo every 48 hours for a total of 3 doses, were analyzed by stratification according to age (< or≥ 60 years), sepsis, or concomitant statin therapy. End points in the trial included cerebral vasospasm and impaired autoregulation on transcranial Doppler ultrasonography, DIDs, and unfavorable outcome at discharge and at 6 months measured with the modified Rankin Scale and Glasgow Outcome Scale. Analyses were performed using the t-test and/or ANOVA for repeated measurements. Results Younger patients (<60 years old) or those without sepsis obtained benefits from EPO by a reduction in vasospasm, impaired autoregulation, and unfavorable outcome at discharge. Compared with nonseptic patients taking EPO, those with sepsis taking EPO had a lower absolute reticulocyte count (nonsepsis vs sepsis, 143.5 vs. 105.8 x 10(9)/L on Day 6; p = 0.01), suggesting sepsis impaired both hematopoiesis and neurovascular protection by EPO. In the EPO group, none of the statin users suffered DIDs (p = 0.078), implying statins may potentiate neuroprotection by EPO. Conclusions Erythropoietin-related neurovascular protection appears to be attenuated by old age and sepsis and enhanced by statins, an important finding for designing Phase III trials.

Platelets transfusions does not help mortality in mild TBI in ASA/Plavix takers

 Am Surg Does platelet administration affect mortality in elderly head-injured patients taking antiplatelet medications?; Monson B, Butler KL, Fortuna GR, Saxe JM, Dolan JP, Markert RJ, McCarthy MC, Downey DM; American Surgeon 75 (11), 1100-3 (Nov 2009)

A significant portion of patients sustaining traumatic brain injury (TBI) take antiplatelet medications (aspirin or clopidogrel), which have been associated with increased morbidity and mortality. In an attempt to alleviate the risk of increased bleeding, platelet transfusion has become standard practice in some institutions. This study was designed to determine if platelet transfusion reduces mortality in patients with TBI on antiplatelet medications. Databases from two Level I trauma centers were reviewed. Patients with TBI 50 years of age or older with documented preinjury use of clopidogrel or aspirin were included in our cohort. Patients who received platelet transfusions were compared with those who did not to assess outcome differences between them. Demographics and other patient characteristics abstracted included Injury Severity Score, Glasgow Coma Scale, hospital length of stay, and warfarin use. Three hundred twenty-eight patients comprised the study group. Of these patients, 166 received platelet transfusion and 162 patients did not. Patients who received platelets had a mortality rate of 17.5 per cent (29 of 166), whereas those who did not receive platelets had a mortality rate of 16.7 per cent (27 of 162) (P = 0.85). Transfusion of platelets in patients with TBI using antiplatelet therapy did not reduce mortality.