Medicine Dosage Calculator: Calculate Safe Doses by Weight
Accurate medicine dosage is crucial for effective treatment and patient safety. This calculator helps determine the correct amount of medication based on a patient's weight, ensuring appropriate therapeutic levels while minimizing risks.
Dosage Calculation Tool
Enter patient weight in kilograms (kg).
Enter the prescribed dosage amount (e.g., mg, ml) per kilogram of body weight.
mg (milligrams)
ml (milliliters)
units
mcg (micrograms)
Select the unit of measurement for the dosage.
Calculation Results
—
Total Dosage: —
Weight in Pounds (lbs): —
Dosage Concentration (if applicable): —
Formula: Total Dosage = Patient Weight (kg) × Dosage per Kilogram
Medicine Dosage Calculation Chart
Chart showing total dosage for a range of patient weights at the specified dosage per kilogram.
Medicine Dosage Calculation Table
Dosage Breakdown by Weight
Patient Weight (kg)
Calculated Total Dosage
Enter values to populate table.
var chartInstance = null; // Global variable to hold the chart instance
function getElement(id) {
return document.getElementById(id);
}
function validateInput(value, id, min, max, errorMessage) {
var errorElement = getElement(id + "Error");
if (value === "") {
errorElement.textContent = "This field cannot be empty.";
return false;
}
var numberValue = parseFloat(value);
if (isNaN(numberValue)) {
errorElement.textContent = "Please enter a valid number.";
return false;
}
if (min !== null && numberValue max) {
errorElement.textContent = errorMessage || "Value cannot be greater than " + max + ".";
return false;
}
errorElement.textContent = "";
return true;
}
function calculateDosage() {
var patientWeight = getElement("patientWeight").value;
var dosagePerKg = getElement("dosagePerKg").value;
var dosageUnit = getElement("dosageUnit").value;
var isValid = true;
if (!validateInput(patientWeight, "patientWeight", 0.1, 500, "Weight must be positive.")) isValid = false;
if (!validateInput(dosagePerKg, "dosagePerKg", 0.01, 1000, "Dosage must be positive.")) isValid = false;
if (!isValid) {
return;
}
var weightKg = parseFloat(patientWeight);
var dosePerKg = parseFloat(dosagePerKg);
var totalDosage = weightKg * dosePerKg;
var weightLbs = weightKg * 2.20462;
getElement("totalDosage").textContent = totalDosage.toFixed(2) + " " + dosageUnit;
getElement("mainResult").textContent = totalDosage.toFixed(2) + " " + dosageUnit;
getElement("weightInPounds").textContent = weightLbs.toFixed(2) + " lbs";
getElement("concentration").textContent = "N/A (depends on drug formulation)"; // Placeholder
// Update Chart
updateChart(dosePerKg, dosageUnit);
// Update Table
updateTable(dosePerKg, dosageUnit);
}
function updateChart(dosePerKg, dosageUnit) {
var ctx = getElement("dosageChart").getContext('2d');
// Generate data for the chart
var weights = [10, 20, 30, 40, 50, 60, 70, 80, 90, 100]; // Sample weights in kg
var dosages = weights.map(function(weight) {
return (weight * dosePerKg).toFixed(2);
});
if (chartInstance) {
chartInstance.destroy(); // Destroy previous chart instance if it exists
}
chartInstance = new Chart(ctx, {
type: 'bar', // Changed to bar for better visualization of discrete dose values
data: {
labels: weights.map(function(w) { return w + " kg"; }),
datasets: [{
label: 'Calculated Dosage (' + dosageUnit + ')',
data: dosages,
backgroundColor: 'rgba(0, 74, 153, 0.6)', // Primary color
borderColor: 'rgba(0, 74, 153, 1)',
borderWidth: 1
}]
},
options: {
responsive: true,
maintainAspectRatio: false,
scales: {
y: {
beginAtZero: true,
title: {
display: true,
text: 'Total Dosage (' + dosageUnit + ')'
}
},
x: {
title: {
display: true,
text: 'Patient Weight (kg)'
}
}
},
plugins: {
legend: {
position: 'top',
},
title: {
display: true,
text: 'Dosage Calculation for Varying Weights'
}
}
}
});
}
function updateTable(dosePerKg, dosageUnit) {
var tableBody = getElement("dosageTableBody");
tableBody.innerHTML = ""; // Clear previous rows
var weights = [10, 20, 30, 40, 50, 60, 70, 80, 90, 100]; // Sample weights in kg
weights.forEach(function(weight) {
var calculatedDose = (weight * dosePerKg).toFixed(2);
var row = tableBody.insertRow();
var cellWeight = row.insertCell(0);
var cellDose = row.insertCell(1);
cellWeight.textContent = weight + " kg";
cellDose.textContent = calculatedDose + " " + dosageUnit;
});
}
function resetCalculator() {
getElement("patientWeight").value = "70";
getElement("dosagePerKg").value = "5";
getElement("dosageUnit").value = "mg";
// Clear error messages
getElement("patientWeightError").textContent = "";
getElement("dosagePerKgError").textContent = "";
getElement("dosageUnitError").textContent = "";
calculateDosage(); // Recalculate with default values
}
function copyResults() {
var mainResult = getElement("mainResult").textContent;
var totalDosage = getElement("totalDosage").textContent;
var weightInPounds = getElement("weightInPounds").textContent;
var concentration = getElement("concentration").textContent;
var formula = "Formula: Total Dosage = Patient Weight (kg) × Dosage per Kilogram";
var copyText = "Medicine Dosage Calculation Results:\n\n" +
"Primary Result (Total Dosage): " + mainResult + "\n" +
"Total Dosage: " + totalDosage + "\n" +
"Weight in Pounds: " + weightInPounds + "\n" +
"Dosage Concentration Assumption: " + concentration + "\n\n" +
"Formula Used:\n" + formula;
// Use a temporary textarea to copy text
var textArea = document.createElement("textarea");
textArea.value = copyText;
textArea.style.position = "fixed"; // Avoid scrolling to bottom of page
textArea.style.opacity = "0";
document.body.appendChild(textArea);
textArea.focus();
textArea.select();
try {
var successful = document.execCommand('copy');
var msg = successful ? 'Results copied to clipboard!' : 'Copying failed!';
// Optionally, display a temporary confirmation message
alert(msg);
} catch (err) {
console.error('Fallback: Oops, unable to copy', err);
alert('Copying failed. Please manually copy the results.');
}
document.body.removeChild(textArea);
}
// Initial calculation and chart rendering on page load
window.onload = function() {
calculateDosage();
// Initialize chart with default values
updateChart(parseFloat(getElement("dosagePerKg").value), getElement("dosageUnit").value);
};