The first Pradaxa lawsuit was filed against drug manufacturer Boehringer Ingelheim last week on behalf of Bertha Bivens, who claims her mother died after suffering a gastrointestinal bleed that Pradaxa allegedly caused. Since the first lawsuit was reported, at least five more have been filed.

Pradaxa (dabigatran) is a blood thinning medication first approved in 2008 by the European Commission for treatment of post-knee surgery and atrial fibrillation. Two years later in October, the U.S. Food and Drug Administration approved Pradaxa for treatment of atrial fibrillation, a condition in which a dysfunctional heartbeat leads to blood clot formulation. These blood clots may cause serious and even deadly conditions if left untreated. For example, a blood clot can cause a stroke if it travels to the brain or a pulmonary embolism if it travels to the lungs.

Shortly after FDA approval, a flood of complaints was filed linking Pradaxa to a number of adverse side effects including gastrointestinal bleeding, internal bleeding, brain hemorrhaging, heart attack, and death. The FDA has not issued a recall, but it has begun to investigate the reported internal bleeding occurrences.

Some researchers pose the argument that Pradaxa’s side effects may be reversible if it contained a reversing agent present such as the one in Warfarin, a traditional and competing blood thinner. Other researchers believe that the reported adverse side effects are caused by healthcare professionals’ improper dosing.

Pradaxa is included in a class of drugs called direct thrombin inhibitors that work by preventing the functionality of the enzyme that causes blood cells to form clots.

In the case Bivens vs. Ingelheim, Bivens alleges that her mother was prescribed Pradaxa in January of 2011 and died from gastrointestinal bleeding three months later. As of November 2011, more than 260 deaths linked to Pradaxa were reported. The majority of these are associated with intense bleeding events.