Worked example

Oral dose - tablets - practice problem 6

The prescriber orders 3 mg of warfarin PO. The pharmacy stocks warfarin in 1 mg tablets.

Ordered dose3 mg

On hand1 mg per tablet

How many tablets should the nurse give?

Answer: 3 tablets

Step-by-step solution

1. Identify what you have and what you want

Have: 1 mg per tablet · Want: 3 mg

2. Set up dimensional analysis so mg cancels

3 mg × ( 1 tablet ÷ 1 mg )

3. Cancel mg and solve

= ( 3 × 1 ) ÷ 1 tablet

= 3 tablets