Merck Proposes New Blood Thinner With Similar Dangers As Pradaxa» Merck & Co. is proposing another new generation blood thinner, similar to Pradaxa, which appears to also pose an increased risk of serious and potentially life-threatening bleeding events. Tags bleedingblood thinnerboehringer ingelheim'sdirect thrombin inhibitorsjohnson & johnsonmarck & copradaxavorapaxarxarelto