How Activase is given or administered depends upon the patient’s weight and what it is being used to treat (such as a stroke, pulmonary embolism, or myocardial infarction. For example, when used to treat a heart attack (myocardial infarction), there are two Activase dose regimens, an accelerated and a 3-hour regimen, with different recommendations depending on if the patient is over 67kg or not. For the accelerated regimen, adults weighing  67 kg or less get a 15 mg IV bolus, followed by 0.75 mg/kg IV (not to exceed 50 mg) infused over 30 minutes, and then 0.5 mg/kg IV (not to exceed 35 mg) over the next 60 minutes Adults greater than or equal to 67 kg get a 15 mg IV bolus, followed by 50 mg IV infused over 30 minutes, and then 35 mg IV infused over the next 60 minutes