Cardiovascular diseases are the leading cause of death globally, making the use of oral anticoagulants for prevention increasingly important. Historically, warfarin has played a significant role in this context. In recent years, introduction of new oral anticoagulants, such as rivaroxaban, apixaban, dabigatran, and edoxaban, has been seen. This study evaluates the risk associated with the use of oral anticoagulants by analyzing spontaneous adverse drug reactions reported to the Portuguese Pharmacovigilance System from 2012 to 2021. The study includes 951 adverse drug reactions reports, with the majority (n = 770; 80.97%) classified as serious. Of the 770 serious adverse drug reactions reports, the most commonly reported seriousness criterion was “Clinically Important” (n = 350; 45.45%). In terms of demographics, there was a higher reporting rate among the elderly population, with a greater prevalence of females. The System Organ Class group with the highest number of adverse drug reactions was “Gastrointestinal disorders,” with the most commonly reported Preferred Term being “Gastrointestinal hemorrhage,” and dabigatran was the most frequently reported drug. In summary, oral anticoagulants have adverse drug reactions that require continuous monitoring. Accurate identification and monitorization of adverse drug reactions is an important starting point to improve drug safety in population.