An new study found that the blood thinner, Pradaxa (dabigatran etexilate mesylate), may increase risks viral infections, as well as increasing the severity of these infections.
University of North Carolina researchers discovered that the blood thinner blocks a critical component in the human blood clotting system and that this may increase viral infection risks. Increased risks were seen for the flu and myocarditis, which is a viral heart infection that is a significant cause of sudden death in children and young adults, News-Medical said.
For about five decades, warfarin—also known by the brand name, Coumadin—was prescribed to patients diagnosed with atrial fibrillation, an irregularity of the heartbeat, and others at risk of forming potentially fatal blood clots, explained News-Medical. Warfarin is an anticoagulant medication.
Pradaxa is a blood-thinning medication used to reduce risks of stroke and blood clots in patients with non-valvular atrial fibrillation (AF), a common heart rhythm abnormality; Pradaxa is not approved for patients with atrial fibrillation caused by heart valve problems. Pradaxa also inhibits thrombin, which is, explained News-Medical, the central coagulation activator in the body’s blood clotting system.
Normal coagulation activities are interrupted when thrombin activity is blocked. Clot formation is reduced; however, the study suggests that immune responses are also impacted. “Our findings show that blocking thrombin reduces the innate immune response to viral infection,” said study senior author, Nigel Mackman, PhD. Mackman is the John C. Parker Distinguished Professor of Medicine in the division of hematology and director of the UNC McAllister Heart Institute, said News-Medical. “The use of the new generation of blood thinners might increase the risk and severity of flu and myocarditis,” he added.
Mackman also said that, “We are now determining if the traditional long term anticoagulant warfarin has the same effect on viral infection or is this specific to the new blood thinner,” according to News-Medical. A report on the research appears in the March 2013 issue of The Journal of Clinical Investigation.
Both Pradaxa and warfarin can cause internal bleeding, but there are readily available antidotes for warfarin bleeding. A growing number of Pradaxa bleeding lawsuits allege the drug caused serious, uncontrollable bleeding side effects, including gastrointestinal bleeding and cerebral hemorrhaging for which there is no reversal agent.
Other research revealed that Pradaxa should not be used to prevent stroke or blood clots in patients implanted with mechanical heart valves and the U.S. Food and Drug Administration (FDA) informed health care professionals and the public of the dangers of Pradaxa for patients with mechanical heart valves. A clinical trial in Europe was halted because Pradaxa users were more likely to experience strokes, heart attacks, and blood clots forming on the heart devices than were users of warfarin. Pradaxa users also experienced more bleeding after valve surgery than those taking warfarin.
Despite a growing number of serious gastrointestinal bleed reports linked to Pradaxa, the FDA argues that the blood thinner, manufactured by Behringer Ingelheim, is safe when used as directed. Pradaxa, approved slightly more than two years ago, has been associated with a large number of post-marketing incidences of gastrointestinal bleeding; however, the FDA states that it has concluded that Pradaxa bleeding rates are no higher that what is reported in patients taking warfarin, a decades-old and traditional blood thinner treatment. Yet, Pradaxa has been linked to over 500 deaths and even more side effect reports than any other drug, noted Forbes previously, citing the Institute for Safe Medicine Practices (ISMP). One major problem with Pradaxa–unlike warfarin—is that there is no antidote for a Pradaxa bleed.