tPA Calculator

Written by Great Medico

Updated September 24, 2026 •2 min read

Share Print Save

Medication calculations can look deceptively simple: one unit or branch can change the answer. tPA Calculator keeps the exact inputs used by this calculator visible so the result can be checked rather than trusted blindly.

What this calculator does

tPA Calculator uses Weight to produce the total tpa (alteplase) used by this calculator. It only uses the fields shown in this calculator; it does not silently add tests, diagnoses, symptoms, or clinical variables that are absent from the interface. tPA flow: weight only; total alteplase dose is 0.9 mg/kg capped at 90 mg, with 10% bolus and 90% infusion.

How to use it

Enter or select Weight. Double-check the medication, route or formulation choices, weight/unit conversions, and concentration before relying on the output. If an input is unknown, it is better to leave the calculation unresolved than to invent a value.

How the calculation works

Alteplase dose is 0.9 mg/kg × body weight, capped at 90 mg. The calculator then splits that total into 10% for the initial bolus and 90% for the remaining infusion.

Example

Using the calculator’s prefilled demonstration values, the primary output is 63 mg, labeled “Total tPA (alteplase)”; 10% bolus is 6.3 mg and 90% infusion is 56.7 mg. That sample is useful for checking the calculation path, but real interpretation should use verified measurements from the same clinical or study context.

How to interpret the result

The milligram result is the dose split for the weight entered if an alteplase stroke protocol has already been selected by the treating team. It does not mean the patient qualifies for alteplase.

Limitations and notes

This calculator only performs the classic alteplase weight-based dose split. It does not decide whether a patient has acute ischemic stroke, whether thrombolysis is indicated, timing eligibility, imaging criteria, blood-pressure eligibility, contraindications, or whether another thrombolytic protocol is preferred.