Nursing Math and Medication Dosage Calc. by

Metric Mnemonic

demarco10 — 2025-02-06 14:18:41 UTC

Remember: You must have this memorized!

Ratios

demarco10 — 2025-02-06 14:25:18 UTC

In nursing math, remember that there are always constants (things we cannot change)! For example, we cannot change: 1. The ordered dose, or 2. The medication concentration available.

Yet, we CAN solve for the desired dose or volume by using ratios!

A Deeper Dive...

demarco10 — 2025-02-06 14:28:59 UTC

You will only be able to create two equal sides to the equation by having all units of measurement match. We must be converting 'like to like'.

For ex., in the example above: Your first step must be converting grams to milligrams. This is because our order is for a dose in milligrams (therefore, our answer must be in that unit of measurement!)

American to Metric Conversion Ratios

demarco10 — 2025-02-06 14:33:14 UTC

It is important to know these conversions as well, particularly when working with a pediatric population. Many of their medications are prescribed in this manner!

demarco10 — 2025-02-06 14:36:57 UTC

To convert KG to Pounds: Multiply by 2.2

To convert Pounds to KG: Divide by 2.2

Another Example...

demarco10 — 2025-02-06 15:08:43 UTC

In this example, we have an order for a 25mg dose, but have 50mg tablets available. We can set up the ratio to create a 'like to like' equation. We then cross multiply and divide to solve for X.