How To Calculate Dosage Formula

Dosage Formula:

\[ \text{Dose} = \frac{\text{Desired dose}}{\text{Stock concentration}} \times \text{Volume} \]

Desired dose (mg/kg):

mg/kg

Patient weight:

Stock concentration:

mg/ml

Volume:

Dose (units):

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is the Dosage Formula?

The dosage formula calculates the amount of medication to administer based on the desired dose, patient weight, medication concentration, and volume. It's essential for safe and effective medication administration.

2. How Does the Calculator Work?

The calculator uses the dosage formula:

\[ \text{Dose} = \frac{\text{Desired dose} \times \text{Patient weight}}{\text{Stock concentration}} \times \text{Volume} \]

Where:

\( \text{Desired dose} \) — Target dose per kg of body weight (mg/kg)
\( \text{Patient weight} \) — Patient's weight in kilograms (kg)
\( \text{Stock concentration} \) — Concentration of medication (mg/ml)
\( \text{Volume} \) — Volume to administer (ml)

Explanation: The formula first calculates the total required dose based on patient weight, then determines how much volume of the stock solution contains that dose.

3. Importance of Accurate Dosage Calculation

Details: Precise dosage calculation is critical for medication safety - too little may be ineffective, while too much can be dangerous. This is especially important for weight-based medications in pediatrics and critical care.

4. Using the Calculator

Tips: Enter all values in the specified units. Double-check medication concentrations as they vary between formulations. Always verify calculations, especially for high-risk medications.

5. Frequently Asked Questions (FAQ)

Q1: What if my medication concentration is in different units?
A: Convert all units to be consistent (mg/kg and mg/ml). For example, if concentration is 1g/100ml, convert to 10mg/ml.

Q2: How should I round the final dose?
A: Round to the nearest measurable amount based on your administration device (e.g., syringe markings).

Q3: Does this work for all medications?
A: This works for most weight-based medications, but some drugs require additional considerations (e.g., BSA calculations).

Q4: What about pediatric doses?
A: The same formula applies but be especially careful with decimal places and small volumes in pediatric patients.

Q5: Should I use actual or ideal body weight?
A: It depends on the medication - follow specific medication guidelines (e.g., use ideal weight for some antibiotics in obese patients).