Calculating the infusion rate for Dopamine is a critical skill in emergency medicine and intensive care. Because Dopamine is dosed in micrograms per kilogram per minute (mcg/kg/min), but IV pumps are programmed in milliliters per hour (mL/hr), a multi-step conversion is required.
The Standard Formula:
Infusion Rate (mL/hr) = [Dose (mcg/kg/min) × Weight (kg) × 60 min] / Concentration (mcg/mL)
Steps for Manual Calculation
Determine Concentration: Divide the total milligrams of Dopamine by the total milliliters of the IV bag. Then multiply by 1,000 to convert mg to mcg.
Example: 400mg / 250mL = 1.6 mg/mL = 1,600 mcg/mL.
Calculate mcg per minute: Multiply the ordered dose by the patient's weight.
Example: 5 mcg/kg/min × 70 kg = 350 mcg/min.
Calculate mcg per hour: Multiply the mcg/min by 60 minutes.
Example: 350 mcg/min × 60 = 21,000 mcg/hr.
Find mL per hour: Divide the total mcg/hr by the concentration (mcg/mL).
Example: 21,000 mcg/hr / 1,600 mcg/mL = 13.1 mL/hr.
Dopamine Dosage Ranges
Dosage Range
Rate (mcg/kg/min)
Primary Effect
Low Dose
0.5 – 2 mcg/kg/min
Renal vasodilation (Dopaminergic)
Medium Dose
2 – 10 mcg/kg/min
Increased cardiac output (Beta-1)
High Dose
> 10 mcg/kg/min
Vasoconstriction (Alpha-1)
Common Troubleshooting and Tips
Always verify the concentration of the premixed bag. The most common standard concentrations are 400 mg in 250 mL or 800 mg in 500 mL, both of which result in a concentration of 1,600 mcg/mL. Always use an infusion pump for Dopamine administration to ensure accuracy and prevent tissue necrosis from extravasation.
function calculateDopamine() {
var weight = parseFloat(document.getElementById('patientWeight').value);
var dose = parseFloat(document.getElementById('desiredDose').value);
var mg = parseFloat(document.getElementById('drugAmount').value);
var ml = parseFloat(document.getElementById('bagVolume').value);
var resultArea = document.getElementById('resultArea');
var mlResult = document.getElementById('mlResult');
var concentrationDisplay = document.getElementById('concentrationDisplay');
if (isNaN(weight) || isNaN(dose) || isNaN(mg) || isNaN(ml) || weight <= 0 || mg <= 0 || ml <= 0) {
alert("Please enter valid positive numbers for all fields.");
return;
}
// 1. Calculate concentration in mcg/mL
// Concentration = (mg * 1000) / mL
var totalMcg = mg * 1000;
var concentrationMcgPerMl = totalMcg / ml;
// 2. Calculate mL/hr
// Rate = (Dose * Weight * 60) / Concentration
var rateMlHr = (dose * weight * 60) / concentrationMcgPerMl;
// Display results
mlResult.innerHTML = rateMlHr.toFixed(2) + " mL/hr";
concentrationDisplay.innerHTML = "Calculated Concentration: " + concentrationMcgPerMl.toFixed(0) + " mcg/mL";
resultArea.style.display = "block";
}