Calculate the standard alteplase (tPA) dose for acute ischemic stroke: 0.9 mg/kg up to 90 mg, with 10% as a bolus and the rest infused over 60 minutes.
Result
How to use this tool
Enter the patient’s body weight in kilograms.
Note the hours since symptom onset under Advanced options.
Read the total dose, the 10% bolus and the 90% infusion.
Confirm imaging, blood pressure and contraindications separately before any treatment.
Formula & worked example
At 80 kg the dose is 0.9 x 80 = 72 mg: a 7.2 mg bolus over 1 minute, then 64.8 mg infused over 60 minutes.
Limitations — read this before you rely on it
Dose arithmetic only: this tool does not assess eligibility, hemorrhage risk, blood pressure, anticoagulant use or stroke mimics. Alteplase is a high-risk drug given only in equipped stroke settings. Clinician use only. This tool is for education only and is not medical advice. Talk to a clinician about any result that worries you, and never change treatment because of a calculator result.
Frequently asked questions
0.9 mg/kg of body weight up to a maximum of 90 mg, with 10% given as a bolus over 1 minute and the rest infused over 60 minutes.
Up to 4.5 hours from symptom onset for standard use, with earlier treatment giving better outcomes. Later or wake-up strokes need specialist imaging-based selection.
No. It only computes the dose. Imaging to exclude hemorrhage, blood pressure limits, recent surgery or bleeding, and other contraindications must all be checked separately.
Tenecteplase is an alternative thrombolytic with a different regimen (0.25 mg/kg single bolus, maximum 25 mg) and is not covered by this calculator.
Clinicians managing acute stroke. It is a dose arithmetic aid, not a treatment decision.