ATLAND Medical Learning
Drug Dosage Calculation
Nursing Key Points and Calculations
Points to note:
1. Fill in the blank is used for medication, IV flow rate, and intake-output calculation.
2. The unit of measure needed for final answer is always given.
3. Rounding an answer should be done at the end of the calculation.
4. The metric system is the common system of measurement. It covers gram for weight, meter
for length and distance, and litre for volume.
5. Other systems of measurement include:
Milliequivalent (mEq) which is an expression of the number of grams of a
medication contained in 1 milligram of solution.
Unit (U) which measures a medication in terms of its action, not its physical weight
for example insulin, penicillin, and heparin sodium.
6. Convert values between metric system
7. Convert units between systems
Methods for Drug Dosage Calculations:
1. Standard method
It is the commonly used method
D – Desired dose is the ordered dose,
H - Dose on hand is what is available or labelled,
V- Vehicle is the form in which the drug comes.
X=DxV
H
Demonstration:
Physician order acetaminophen 1000 mg, and the nurse find acetaminophen 250 mg in 5
mL. Calculate amount to give.
Desired (D) = 1000 mg
Hand (H) = 250 mg
Vehicle (V) = 5 mL
Drug Dosage Calculation
Nursing Key Points and Calculations
Points to note:
1. Fill in the blank is used for medication, IV flow rate, and intake-output calculation.
2. The unit of measure needed for final answer is always given.
3. Rounding an answer should be done at the end of the calculation.
4. The metric system is the common system of measurement. It covers gram for weight, meter
for length and distance, and litre for volume.
5. Other systems of measurement include:
Milliequivalent (mEq) which is an expression of the number of grams of a
medication contained in 1 milligram of solution.
Unit (U) which measures a medication in terms of its action, not its physical weight
for example insulin, penicillin, and heparin sodium.
6. Convert values between metric system
7. Convert units between systems
Methods for Drug Dosage Calculations:
1. Standard method
It is the commonly used method
D – Desired dose is the ordered dose,
H - Dose on hand is what is available or labelled,
V- Vehicle is the form in which the drug comes.
X=DxV
H
Demonstration:
Physician order acetaminophen 1000 mg, and the nurse find acetaminophen 250 mg in 5
mL. Calculate amount to give.
Desired (D) = 1000 mg
Hand (H) = 250 mg
Vehicle (V) = 5 mL
