Which anticoagulant requires frequent monitoring of serum bleeding times?

Heparin is a traditional anticoagulant that requires frequent monitoring of serum bleeding times, specifically the activated partial thromboplastin time (aPTT). This monitoring is essential because heparin has a variable effect based on patient-specific factors such as body weight and other medical conditions. Since its anticoagulant effect can significantly differ among individuals and the dosing can lead to either bleeding complications or inadequate anticoagulation, regular aPTT checks help ensure that the patient remains within the therapeutic range.

Additionally, while low-molecular-weight heparins have a more predictable pharmacokinetic profile that does not typically necessitate routine monitoring, and newer oral anticoagulants like rivaroxaban and warfarin have different monitoring requirements, heparin remains unique in its need for frequent aPTT assessments to maintain safe and effective anticoagulation during treatment.