TUESDAY, Sept. 21, 2010 (HealthDay News) -- A new study finds it's safe to take the blood thinner Plavix with proton-pump inhibitors like Nexium, contrary to recent research that said the combination compromised Plavix's effectiveness.
"We looked into this highly debated area of clopidogrel [Plavix] and proton-pump inhibitors," said lead researcher Dr. Mette Charlot from the department of cardiology at Copenhagen University Hospital Gentofte in Hellerup, Denmark."We did not find any evidence of drug interaction."
Proton-pump inhibitors are heartburn drugs. Doctors often prescribe the two drugs in combination to prevent clotting and reduce the risk of stomach bleeding, which can be a serious complication for patients taking Plavix, the researchers said.
This study is larger than studies that found an interaction between the drugs, and this data included patients who were taking PPIs but not Plavix, Charlot noted.
"What we actually found was an increased risk related to the use of proton-pump inhibitors, but we found the risk was the same in patients treated with clopidogrel and patients not treated with clopidogrel," Charlot said.
For the study, published in the Sept. 21 issue of the Annals of Internal Medicine and funded by the Danish Medical Research Counciland the Danish Heart Foundation, Charlot's team collected outcome data on 56,406 patients across Denmark who had a first heart attack between 2000 and 2006. Follow-up was one year.
Sixteen percent were rehospitalized for a heart attack or stroke, or died. Of the 44 percent of patients who took Plavix, 27 percent also took a PPI, the researchers say.
Patients taking both medications had a 29 percent increased risk of rehospitalization for a heart attack or stroke, or death. However, among patients taking only a PPI, the risk of these adverse events was also 29 percent, the researchers found.
The researchers concluded that the increased risk of a heart attack, stroke or death is associated with PPIs, and not the combination of Plavix and a PPI.
"We are confident that the feared interaction between the two drugs does not happen," Charlot said. "We believe that patients who have an indication for PPI treatment should definitely be treated with PPIs to avoid the risk of gastrointestinal bleeding," she added.
Dr. James Brophy, a professor of medicine and epidemiology at the Royal Victoria Hospital in Montreal, Canada, said this new research carries more weight than the earlier studies.
This study "appears to be of superior quality to several previous reports," said Brophy, author of an accompanying journal editorial. "There is not high quality evidence supporting a meaningful drug interaction between clopidogrel and PPIs," he said.
"While unnecessary drug prescribing is always to be avoided, the current evidence suggests that patients taking clopidogrel can take a PPI," Brophy said.
Additional studies would be helpful, Brophy added, "but in the interim, the dangers of bleeding from avoiding PPIs may well be greater than any cardiac risks from inhibiting clopidogrel."
For more information on the Plavix-PPI combo, visit the U.S. Food and Drug Administration.