Mixing acid blockers, anti-clotting drug risky
POSTED May 8, 2009 - 16:49 | POSTED BY Jyoti Pal
Last edited by Harpreet Bhagrath on May 8, 2009 - 17:47
Heartburn drugs, from a class of drugs called the Proton Pump Inhibitor (PPI), impair the anti-clotting benefits of clopidogrel, the active ingredient in Plavix, when taken together, researchers explained.
Study details
Medical records of 16,690 patients taking clopidogrel for a year following stent implantation were scrutinized for the purpose.
While Clopidogrel is the common prescription following a stent implantation, a tiny drug-coated or bare metal wire mesh tube that prop opens clogged arteries, PPIs are prescribed to treat adverse effects of clopidogrel like nausea and stomach acid reflux.
Compatibility of four proton pump inhibitors, namely AstraZeneca's (AZN.L) Nexium and Prilosec, Takeda Pharmaceutical’s (4502.T) Prevacid and Wyeth's (WYE.N) Protonix were assessed with Plavix.
Follow-up analysis revealed that patients taking Plavix and any of the four PPIs were 50 percent more likely to experience an increase in the risk of hospitalization for heart attack, stroke, unstable angina or re-procedure for stent implantation, than those only on Plavix.
“Our study highlights a potential interaction between clopidogrel and PPI medication. And it suggests that maybe PPI medication should not just be prescribed routinely or prophylactically in patients who are on aspirin and clopidogrel,” Dr. Steven Bailey, Society for Cardiac Angiography and Interventions (SCAI) president-elect, asserted.
“The proton pump inhibitors (PPIs) neutralize more than stomach acid. They interfere with enzymes in the liver that metabolize clopidogrel, reducing its anti-clotting effects,” he said.
The US Food and drug Administration has now called for a larger trial to determine which categories of patients are most affected by the PPI and whether newer PPIs such as Aciphex and Kapidex react similarly.
Meanwhile, medics recommend that stent patients should use alternative medications like histaminergic (H2), blockers such as Zantac and Tagamet or antacids for heartburn and acid reflux symptoms.
The results of the study were presented at a meeting of the SCAI in Las Vegas on Wednesday.
