Worked example

Oral dose - tablets - practice problem 11

The prescriber orders 0.25 mg of digoxin PO. The pharmacy stocks digoxin in 0.125 mg tablets.

Ordered dose0.25 mg

On hand0.125 mg per tablet

How many tablets should the nurse give?

Answer: 2 tablets

Step-by-step solution

1. Identify what you have and what you want

Have: 0.125 mg per tablet · Want: 0.25 mg

2. Set up dimensional analysis so mg cancels

0.25 mg × ( 1 tablet ÷ 0.125 mg )

3. Cancel mg and solve

= ( 0.25 × 1 ) ÷ 0.125 tablet

= 2 tablets