# tPA Dose Calculator (Alteplase and Tenecteplase for Stroke)

URL: https://speedycalculator.com/calculators/health/tpa/
Last updated: 2026-10-30

> The tPA dose calculator works out the alteplase dose for acute ischaemic stroke (0.9 mg/kg, maximum 90 mg, 10% as a bolus over 1 minute and the rest over 60 minutes) and the tenecteplase dose (0.25 mg/kg, maximum 25 mg). For professional reference only.

## Inputs

- Weight (kg, lb, st, g)

## Results

- Alteplase total dose
- Alteplase bolus (10%)
- Alteplase infusion over 60 min (90%)
- Infusion rate (1 mg/mL)
- Tenecteplase dose

## Formula

```
Alteplase: total = 0.9 mg/kg (max 90 mg); bolus = 10% over 1 min; infusion = 90% over 60 min
Tenecteplase (stroke): 0.25 mg/kg single bolus (max 25 mg)
```

## Explanation

Clot-busting drugs restore blood flow in ischaemic stroke when given within 4.5 hours of symptom onset in eligible patients. Accurate weight is essential; doses are always checked by two clinicians.

### How to use the tPA Dose Calculator

- **Weight**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Enter the patient's weight. Strict eligibility criteria and local protocols apply.

### What each result means

- **Alteplase total dose** = min(0.9×[Weight], 90)
- **Alteplase bolus (10%)** = [Alteplase total dose]×0.1
- **Alteplase infusion over 60 min (90%)** = [Alteplase total dose]×0.9
- **Infusion rate (1 mg/mL)** = [Alteplase infusion over 60 min (90%)]
- **Tenecteplase dose** = min(0.25×[Weight], 25)

### Example values

How the main result changes when **Weight** changes and everything else stays at the example values above:

Weight (kg)Alteplase total dose (mg)403660548072100901209016090
*Health note: this calculator is for education and screening only and is not a diagnosis or treatment advice. Discuss your results with a qualified clinician.*

## Worked example

Inputs — Weight: 80 kg.

Results — **Alteplase total dose = 72 mg**; Alteplase bolus (10%) = 7.2 mg; Alteplase infusion over 60 min (90%) = 64.8 mg; Infusion rate (1 mg/mL) = 64.8 mL/h; Tenecteplase dose = 20 mg.

## Key terms

- **tPA**: Tissue plasminogen activator.

## FAQ

**What is the maximum alteplase dose for stroke?**
90 mg.

**Why is the stroke dose lower than for heart attacks?**
To reduce the risk of brain bleeding.

**Is tenecteplase used for stroke?**
Yes – guidelines now endorse 0.25 mg/kg as an alternative.


## Sources

- [Powers WJ et al. Guidelines for the early management of acute ischemic stroke: 2019 update. Stroke, 2019](https://pubmed.ncbi.nlm.nih.gov/31662037/)