Examples · Reconstitution
Worked example
Reconstitution - practice problem 14
The prescriber orders 250 mg of vancomycin IV. A 1 g vial directs: add 20 mL of diluent to yield 50 mg/mL.
Ordered dose250 mg
Vial1 g
Diluent20 mL
After reconstitution50 mg/mL
How many milliliters should the nurse draw up?
Answer: 5 mL
Step-by-step solution
1. Read the concentration after reconstitution
Add 20 mL diluent → 50 mg per 1 mL
2. Set up dimensional analysis so mg cancels
250 mg × ( 1 mL ÷ 50 mg )
3. Cancel mg and solve
= 250 ÷ 50 mL
= 5 mL
More reconstitution examples