A vial is reconstituted to a final volume of 3 mL and contains 750 mg of drug. The prescription is for 425 mg. What volume should the nurse withdraw?
Correct answer: C. 1.7 mL
- A. 1.2 mL
- B. 1.5 mL
- C. 1.7 mL
- D. 2.0 mL
Explanation
The concentration after reconstitution is 750 mg ÷ 3 mL = 250 mg/mL. The required volume is 425 mg ÷ 250 mg/mL = 1.7 mL. Using the original powder volume instead of the final reconstituted volume would give an incorrect result.
Report an error
The more specific you are, the faster it gets fixed. A source beats an opinion.
Prefer email? support@testustad.com
About Drug Calculations and Dosage
Drug calculations apply measurement systems, unit conversions, dosage formulas, tablet and liquid doses, percentage and ratio strength, and weight based dosing. Work also includes calculating IV flow rates, infusion times and doses for children, while distinguishing the prescribed dose from the available concentration.
Practise Drug Calculations and Dosage
50 free Drug Calculations and Dosage MCQs from Nursing Pharmacology, each with the correct answer and an explanation. Unlimited attempts, no account needed.
Discussion
Stuck on an option, or know a faster way to get there? Ask or explain it here.
No comments yet. Be the first to explain this one.
Exams that ask Nursing Pharmacology questions like this
Nursing Pharmacology is on 8 papers prepared for on TestUstad, and all of them draw the same bank, so this question is worth knowing for every one of them.
More Drug Calculations and Dosage questions
An injection has a ratio strength of 1:500, meaning 1 g of drug is present in 500 mL of solution. How much drug is present in 12 mL?
A solution is labelled 3% w/v. How much drug is present in 80 mL of the solution?
An IV bag contains 1,440 mL and is running at 120 mL per hour. How long will the infusion take to complete?
An adult weighs 72 kg and is prescribed a medicine at 0.08 mg/kg per dose. The injection contains 4 mg/mL. What volume should the nurse administer?
A patient is prescribed 1.2 g of a medicine. The available tablets contain 400 mg each. How many tablets should the nurse administer?
A patient is prescribed 2.5 mg of an oral medicine. The liquid contains 5 mg in 2 mL. What volume should the nurse administer?