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Dimensional Analysis Medication Dose Calculator, Liquid Form

Liquid Medication dose calculator based on Dimensional Analysis also known as Factor-label method. Dimensional Analysis Dose Calculator allows you to calculate normal and weight based Drugs Doses.

Doses liquid medications such as (syrups, emulsions, suspensions etc).

It doesn’t matter what type of units are used in this formula.  You can figure out how many grams to give or how many milligrams to give, micrograms, units, grains, etc.  Remember to be consistent (e.g., don’t mix milligrams with grams).

To calculate solid medication dose Click Here Dimensional Analysis Calculator, For Solid Dose

Dimensional Analysis Dose Calculator

In liquid form medication dose calculation the Dimensional Analysis (or “Factor-Label Method”) applies, a series of conversion factors of equivalency from one system of measurement to another but doesn’t require memorizing specific formulas. This method reduces errors. It can be used for all dosage calculations..

In case if the dose is ordered as mg/kg we need to multiply patient weight to desired amount (ordered dose).

Dimensional Analysis Calculation Formula

Dimensional Analysis doesn’t require memorizing specific formulas. Here are steps on how to set up a DA Equation.

  1. To set up the equation, start with the unit of measure  is needed.
  2. Build the equation by placing information with the same label as the preceding denominator in the numerator
  3. Cancel out all unwanted labels.
  4. Calculate to determine the correctly labelled numeric answer.

IV Dose Calculation Example

An order for digoxin 0.5 mg IV daily is placed. Digoxin 0.25 mg/mL is available from the pharmacy. How many mL will you need to administer a 0.5 mg dose?

Solution:

  • mL  = ?
  • Dose ordered = 0.5 mg
  • Dose available = 0.25 mg/ml
mL?=ml0.25mg×0.5mg=0.5ml0.25=2ml

The answer is 2ml. You would give 2mL.

Click Here for more Dimensional Analysis Practices

Weight Based IV Dose Calculation Example

Medrol 4 mg/kg is ordered for a child weighing 29.45 kg. Medrol is available
as 500 mg/4mL. How many milliliters of medication must the nurse administer?

Solution:

  • mL  = ?
  • Dose ordered = 4 mg/kg
  • Dose available =500 mg/ml
mL?=4ml500mg×4mgkg×31.25kg=500ml500=1ml

The answer is 1ml. You would give 1mL.

Click Here for more Dimensional Analysis Practices

General Tips

  • Check that your answer makes sense clinically.
  • Triple check your work.
  • Have a colleague or pharmacist check your work.
  • Know general therapeutic drug doses for commonly administered medications.

Dose Versus Dosage

The purpose of this page is to determine a single dose not a dosage. Dosage implies a frequency.

Dose

Amount of a medicinal preparation or of radiation to be delivered at one time

Dosage

Determination of the amount and frequency, and number of doses of medication or radiation for a patient.

How to Use dimensional analysis drug dose calculator?

Basic Calculator

  • Enter ordered dose,  Available dose and volume
  • Select measurement
  • Click on “Calculate” button and medication dose will appear below.

Advanced Calculator

  • In case of weight based medication switch on weight unit and enter weight
  • Enter ordered dose,  Available dose and volume select their respective units
  • Click on “Calculate” button and medication dose will appear below.

Click Here to calculate BMI.

Learn More about dosage unit conversions

Dimensional Analysis Dose Calculator