Balance between efficacy and safety is a major concern in therapeutic interventions of patients with acute coronary syndromes. Identifying and managing the risks that may negatively affect this balance can potentially minimize the incidence of morbidity and/or mortality among patients with acute coronary syndromes. Unstable angina and non-ST-elevation myocardial infarction are potentially life-threatening disorders and a major cause of hospitalization and emergency medical care. At the time of presentation, the use of algorithms that provide reasonable assessment of a patient's risk of cardiovascular events, such as the Thrombolysis in Myocardial Infarction risk score, can help clinicians identify which patients will most likely benefit from a specific strategy. The ultimate goal of treatment for non-ST-elevation myocardial infarction is to reduce short- and long-term morbidity and mortality, as well as salvage myocardial cells and cardiac function. Pharmacologic intervention with antiplatelet and/or antithrombotic agents has proven to be effective in achieving this goal in numerous outcome studies. However, clinicians must balance anti-ischemic efficacy with the need to minimize the risk of serious bleeding complications (e.g., hemorrhage). Issues related to safety include timing of the dose, duration of infusion, drug compatibility, errors in estimating a patient's weight and/or age, failure to adjust the dosage based upon renal function, and errors in drug preparation.