Commonly 0.5mL for pens or varied for reconstituted vials.
Injection Instructions:
How to Use the Tirzepatide Dosage Calculator
This calculator is designed to help patients and healthcare providers determine the correct volume to draw into a syringe based on the concentration of Tirzepatide (commonly known by brand names like Mounjaro or Zepbound). Because this medication is administered as a subcutaneous injection, precision is vital for effective blood glucose management and weight loss.
Understanding the Math
The formula used to calculate the volume for your injection is based on the concentration of the medication in the vial. We use the standard U-100 insulin syringe scale, where 100 units equals 1.0 mL.
Calculation: (Desired Dose ÷ Total mg in Vial) × Volume in mL × 100 = Injection Units
Realistic Example
If you have been prescribed a 5 mg dose and your vial contains 10 mg of Tirzepatide dissolved in 0.5 mL of liquid:
5mg (Dose) divided by 10mg (Vial Total) = 0.5
0.5 multiplied by 0.5mL (Volume) = 0.25 mL
0.25 mL converted to units = 25 Units on a standard syringe.
Common Tirzepatide Dosage Schedule
Tirzepatide is typically started at a low dose and increased every 4 weeks to minimize gastrointestinal side effects. A common titration schedule includes:
Month
Weekly Dose
Month 1
2.5 mg
Month 2
5.0 mg
Month 3
7.5 mg
Month 4+
Up to 15 mg
Important Medical Disclaimer: This calculator is for educational purposes only. Always follow the specific instructions provided by your physician or pharmacist. Never change your dose without consulting your healthcare provider. Ensure you are using the correct syringe type (U-100 vs U-40) as mixing them up can lead to significant dosing errors.
function calculateTirzepatide() {
var dose = parseFloat(document.getElementById('desiredDose').value);
var totalMg = parseFloat(document.getElementById('vialMg').value);
var volume = parseFloat(document.getElementById('vialVolume').value);
var resultDiv = document.getElementById('tirzepatideResult');
var resultOutput = document.getElementById('resultOutput');
var resultText = document.getElementById('resultText');
if (isNaN(dose) || isNaN(totalMg) || isNaN(volume) || totalMg <= 0 || volume <= 0) {
alert("Please enter valid positive numbers for all fields.");
return;
}
// Math: (Dose / Total mg) * Volume = mL to inject
// mL to inject * 100 = Units on insulin syringe
var mlToInject = (dose / totalMg) * volume;
var unitsToInject = mlToInject * 100;
// Round to 2 decimal places for units
unitsToInject = Math.round(unitsToInject * 100) / 100;
mlToInject = Math.round(mlToInject * 1000) / 1000;
resultDiv.style.display = 'block';
resultDiv.style.backgroundColor = '#e8f5e9';
resultDiv.style.border = '1px solid #c8e6c9';
resultOutput.innerHTML = unitsToInject + " Units";
resultText.innerHTML = "To receive a " + dose + "mg dose, draw " + unitsToInject + " units (equivalent to " + mlToInject + " mL) into your syringe.";
// Scroll result into view
resultDiv.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}