Medication Dosage Calculator
Calculate safe medication dosages based on body weight. Always consult a healthcare professional.
CRITICAL SAFETY WARNING
This calculator is for informational purposes ONLY and should NEVER replace professional medical advice.
- Always consult a doctor or pharmacist before administering any medication
- Dosages vary based on age, medical condition, and individual factors
- This calculator does not account for drug interactions or contraindications
- Verify all calculations with a healthcare professional
Calculate Dosage
Example: 70 (for 70 kg)
This information should come from your doctor or prescription label
Example: 7 (for 7 days)
What is a Dosage Calculator?
A dosage calculator is a medical tool that helps determine the appropriate amount of medication to administer based on various factors, primarily body weight. This is especially important in pediatric medicine and for medications with a narrow therapeutic index.
Medication dosages are often prescribed in milligrams per kilogram of body weight (mg/kg) rather than fixed amounts. This personalized approach ensures that each patient receives an amount of medication that is both safe and effective for their specific body size.
How Dosage is Calculated
The basic formula for calculating medication dosage is:
Single Dose = Weight (kg) × Dosage (mg/kg)
The daily dose is then calculated by multiplying the single dose by the number of times per day the medication is taken:
Daily Dose = Single Dose × Frequency per day
Finally, the total amount needed for the entire treatment course:
Total Dose = Daily Dose × Duration (days)
Example Calculation
For a child weighing 20 kg, prescribed amoxicillin at 25 mg/kg, twice daily for 7 days:
- Single dose: 20 kg × 25 mg/kg = 500 mg
- Daily dose: 500 mg × 2 = 1000 mg
- Total course: 1000 mg × 7 days = 7000 mg (7 grams)
Why Accurate Dosage Calculation Matters
Underdosing Risks
- Treatment failure
- Antibiotic resistance development
- Prolonged illness
- Disease recurrence
Overdosing Risks
- Toxic side effects
- Organ damage
- Life-threatening complications
- Death in severe cases
Frequently Asked Questions
Why are some medications dosed by weight?
Weight-based dosing accounts for differences in body size, metabolism, and distribution of medication in the body. This is particularly important for children, whose bodies process drugs differently than adults. It ensures that each person receives a therapeutic dose that is effective yet safe.
Can I use adult dosages for children?
No! Children are not simply "small adults." Their organs are still developing, and they metabolize medications differently. Always use pediatric dosing guidelines and consult a pediatrician. Never estimate or guess children's dosages.
What if I miss a dose?
If you miss a dose, take it as soon as you remember. However, if it's almost time for your next dose, skip the missed one and continue with your regular schedule. Never double up on doses to make up for a missed one, as this can lead to overdose. Always consult your healthcare provider for specific guidance.
Are liquid medications different from pills?
Liquid medications require careful measurement. Always use the provided measuring device (oral syringe, cup, or dropper), not household spoons which vary in size. Pay attention to the concentration (mg/mL) as different formulations may have different concentrations requiring different volumes.
How do I know if my dosage is too high?
Signs of excessive dosage may include nausea, vomiting, dizziness, confusion, irregular heartbeat, or difficulty breathing. If you experience any unusual symptoms after taking medication, contact your healthcare provider or poison control immediately. In emergencies, call emergency services.
Related Resources
Disclaimer: Disclaimer: This calculator is for educational purposes only. Always consult healthcare professionals for medical advice and treatment decisions.