🩹 Introduction
Medication calculations are one of the most critical components of nursing practice and the NCLEX exam. Nurses must be confident in calculating dosages, IV flow rates, and safe medication administration to prevent medication errors. This NCLEX Medication Calculations Practice set includes 100 high-yield questions designed to strengthen your problem-solving skills in real clinical situations. Each question comes with clear rationales to help you understand the “why” behind every answer — making it ideal for students preparing for the NCLEX-RN or NCLEX-PN exams.
🧮 NCLEX Medication Calculations Practice Questions
1. A doctor orders 500 mg of amoxicillin. The available dose is 250 mg per tablet. How many tablets should the nurse administer?
A. 1 tablet
B. 2 tablets ✅
C. 3 tablets
D. 4 tablets
Rationale: 500 ÷ 250 = 2. The nurse must give 2 tablets to achieve the prescribed dose.
2. A patient needs 1.2 g of ceftriaxone. The vial reads 600 mg/mL. How many mL should the nurse give?
A. 1 mL
B. 1.5 mL
C. 2 mL ✅
D. 2.5 mL
Rationale: 1.2 g = 1200 mg → 1200 ÷ 600 = 2 mL.
3. The order reads 25 mg of diphenhydramine IM. The vial reads 50 mg/mL. How many mL should be given?
A. 0.25 mL
B. 0.3 mL
C. 0.5 mL ✅
D. 1 mL
Rationale: 25 ÷ 50 = 0.5 mL.
4. A patient is prescribed 0.25 mg of digoxin. Available: 0.125 mg tablets. How many tablets should be administered?
A. 1
B. 1.5
C. 2 ✅
D. 2.5
Rationale: 0.25 ÷ 0.125 = 2 tablets.
5. The order is for 500 mg of acetaminophen every 6 hours. Each tablet contains 250 mg. How many tablets are given per dose?
A. 1
B. 2 ✅
C. 3
D. 4
Rationale: 500 ÷ 250 = 2 tablets.
6. The physician orders 75 mg of meperidine IM. The vial label states 100 mg/mL. How many mL will you administer?
A. 0.25 mL
B. 0.5 mL
C. 0.75 mL ✅
D. 1 mL
Rationale: 75 ÷ 100 = 0.75 mL.
7. The order reads: administer 30 units of insulin using a U-100 insulin syringe. How many mL will you inject?
A. 0.1 mL
B. 0.2 mL
C. 0.3 mL ✅
D. 0.4 mL
Rationale: U-100 = 100 units/mL. 30 ÷ 100 = 0.3 mL.
8. A doctor orders 250 mL of IV fluid over 2 hours. What is the flow rate in mL/hr?
A. 100 mL/hr
B. 125 mL/hr ✅
C. 150 mL/hr
D. 200 mL/hr
Rationale: 250 ÷ 2 = 125 mL/hr.
9. The physician orders 1000 mL of NS to infuse over 8 hours. What is the infusion rate?
A. 100 mL/hr
B. 120 mL/hr
C. 125 mL/hr ✅
D. 150 mL/hr
Rationale: 1000 ÷ 8 = 125 mL/hr.
10. The order: 50 mg of medication in 100 mL D5W over 30 minutes. The infusion pump rate is?
A. 100 mL/hr
B. 150 mL/hr
C. 200 mL/hr ✅
D. 250 mL/hr
Rationale: 100 ÷ 0.5 = 200 mL/hr.
11. You are to give 600 mg of ibuprofen. The tablets are 200 mg each. How many tablets will you give?
A. 2
B. 3 ✅
C. 4
D. 5
Rationale: 600 ÷ 200 = 3 tablets.
12. A patient is prescribed 0.5 g of erythromycin. The available suspension is 250 mg/5 mL. How many mL are required?
A. 5 mL
B. 7.5 mL
C. 10 mL ✅
D. 12 mL
Rationale: 0.5 g = 500 mg → (500 × 5) ÷ 250 = 10 mL.
13. Order: 1 mg lorazepam IV. The vial states 2 mg/mL. How many mL should be given?
A. 0.25
B. 0.5 ✅
C. 0.75
D. 1
Rationale: 1 ÷ 2 = 0.5 mL.
14. The doctor orders 0.4 mg nitroglycerin sublingual. Tablets available: 0.2 mg. How many tablets will the nurse give?
A. 1
B. 2 ✅
C. 3
D. 4
Rationale: 0.4 ÷ 0.2 = 2 tablets.
15. Ordered: 120 mg furosemide. Stock: 40 mg tablets. How many tablets to administer?
A. 1
B. 2
C. 3 ✅
D. 4
Rationale: 120 ÷ 40 = 3 tablets.
16. An IV bag of 1000 mL NS is to run at 75 mL/hr. How long will it take to infuse completely?
A. 10 hrs
B. 12 hrs
C. 13 hrs 20 min ✅
D. 15 hrs
Rationale: 1000 ÷ 75 = 13.3 hours ≈ 13 hours 20 minutes.
17. Doctor orders 250 mg vancomycin IVPB in 100 mL over 1 hour. The rate is:
A. 100 mL/hr ✅
B. 125 mL/hr
C. 150 mL/hr
D. 200 mL/hr
Rationale: 100 ÷ 1 = 100 mL/hr.
18. Ordered 0.5 L of IV fluid over 2 hours. How many mL/hr should the pump be set to?
A. 100
B. 200 ✅
C. 250
D. 300
Rationale: 0.5 L = 500 mL → 500 ÷ 2 = 250 mL/hr.
19. Ordered: 60 mg prednisone PO. Tablets: 20 mg. How many tablets to give?
A. 2
B. 3 ✅
C. 4
D. 5
Rationale: 60 ÷ 20 = 3 tablets.
20. The nurse must administer 800 mg cefazolin IV. The reconstituted vial reads 500 mg/mL. How many mL are required?
A. 1
B. 1.5 ✅
C. 2
D. 2.5
Rationale: 800 ÷ 500 = 1.6 ≈ 1.5 mL.
21. Ordered: 0.3 g gentamicin. Stock: 40 mg/mL. How many mL should the nurse give?
A. 5
B. 6.5
C. 7.5 ✅
D. 8
Rationale: 0.3 g = 300 mg → 300 ÷ 40 = 7.5 mL.
22. A patient is prescribed 2 g cefotaxime. The vial contains 1 g/2 mL. How many mL should be administered?
A. 2
B. 3
C. 4 ✅
D. 5
Rationale: 2 g = 2 × 1 g → 2 × 2 = 4 mL.
23. The order is for 150 mg phenytoin. Vial reads 50 mg/mL. How many mL should be given?
A. 1
B. 2
C. 3 ✅
D. 4
Rationale: 150 ÷ 50 = 3 mL.
24. The order is for 1.5 g ampicillin. Vial contains 500 mg/mL. How many mL are needed?
A. 2
B. 3 ✅
C. 4
D. 5
Rationale: 1.5 g = 1500 mg → 1500 ÷ 500 = 3 mL.
25. Ordered: 125 mg methylprednisolone. Available: 250 mg/mL. How many mL should be drawn?
A. 0.25 mL
B. 0.4 mL
C. 0.5 mL ✅
D. 0.75 mL
Rationale: 125 ÷ 250 = 0.5 mL.
🧮 Part 2: NCLEX Medication Calculations Practice Questions (26–50)
26. The doctor orders 500 mg of vancomycin in 250 mL NS over 2 hours. What is the infusion rate?
A. 100 mL/hr
B. 125 mL/hr ✅
C. 150 mL/hr
D. 200 mL/hr
Rationale: 250 ÷ 2 = 125 mL/hr.
27. Ordered: 90 mg gentamicin IV. Stock: 40 mg/mL. How many mL to give?
A. 1
B. 2
C. 2.25 ✅
D. 3
Rationale: 90 ÷ 40 = 2.25 mL.
28. The physician orders 1000 mL of IV fluid over 5 hours. What is the flow rate?
A. 150 mL/hr
B. 175 mL/hr
C. 200 mL/hr ✅
D. 225 mL/hr
Rationale: 1000 ÷ 5 = 200 mL/hr.
29. The order: 400 mg ibuprofen PO. The available dose: 200 mg tablets. How many tablets are needed?
A. 1
B. 2 ✅
C. 3
D. 4
Rationale: 400 ÷ 200 = 2 tablets.
30. Doctor orders 0.6 mg digoxin. Tablets: 0.3 mg. How many tablets should the nurse give?
A. 1
B. 2 ✅
C. 3
D. 4
Rationale: 0.6 ÷ 0.3 = 2 tablets.
31. Ordered 1.5 g cefuroxime. Available: 750 mg/mL. How many mL should be administered?
A. 1
B. 1.5
C. 2 ✅
D. 2.5
Rationale: 1.5 g = 1500 mg → 1500 ÷ 750 = 2 mL.
32. Ordered: 25 mg diazepam IV. The vial reads 5 mg/mL. How many mL should be administered?
A. 2
B. 4
C. 5 ✅
D. 6
Rationale: 25 ÷ 5 = 5 mL.
33. The order: 600 mL of IV fluid over 3 hours. The infusion rate is:
A. 150 mL/hr
B. 175 mL/hr
C. 200 mL/hr ✅
D. 250 mL/hr
Rationale: 600 ÷ 3 = 200 mL/hr.
34. The physician orders 250 mg of medication. Available: 125 mg/mL. How many mL should be given?
A. 1
B. 2 ✅
C. 2.5
D. 3
Rationale: 250 ÷ 125 = 2 mL.
35. Ordered: 75 mg pethidine IM. The vial reads 50 mg/mL. How many mL to give?
A. 1
B. 1.25
C. 1.5 ✅
D. 1.75
Rationale: 75 ÷ 50 = 1.5 mL.
36. Doctor orders 800 mg cefazolin IV. The vial reads 400 mg/mL. How many mL should be administered?
A. 1
B. 2 ✅
C. 2.5
D. 3
Rationale: 800 ÷ 400 = 2 mL.
37. Ordered 0.25 g ampicillin. Stock: 125 mg/mL. How many mL will you give?
A. 1
B. 2 ✅
C. 3
D. 4
Rationale: 0.25 g = 250 mg → 250 ÷ 125 = 2 mL.
38. The order: 0.75 L IV NS over 6 hours. Flow rate?
A. 100 mL/hr
B. 120 mL/hr ✅
C. 125 mL/hr
D. 150 mL/hr
Rationale: 0.75 L = 750 mL → 750 ÷ 6 = 125 mL/hr ≈ 120.
39. A doctor orders 1.5 g of ceftriaxone. Available: 500 mg/mL. How many mL to give?
A. 2
B. 3 ✅
C. 4
D. 5
Rationale: 1.5 g = 1500 mg → 1500 ÷ 500 = 3 mL.
40. The order: 15 mg morphine IM. Vial: 10 mg/mL. How many mL are given?
A. 0.5
B. 1.0
C. 1.5 ✅
D. 2
Rationale: 15 ÷ 10 = 1.5 mL.
41. Ordered: 0.4 mg atropine. Stock: 0.8 mg/mL. How many mL to administer?
A. 0.25
B. 0.4
C. 0.5 ✅
D. 0.75
Rationale: 0.4 ÷ 0.8 = 0.5 mL.
42. The physician orders 2.4 million units penicillin G IM. Vial: 1.2 million units/mL. How many mL to give?
A. 1
B. 2 ✅
C. 2.5
D. 3
Rationale: 2.4 ÷ 1.2 = 2 mL.
43. Ordered: 0.75 g vancomycin. Stock: 500 mg/mL. How many mL?
A. 1
B. 1.5 ✅
C. 2
D. 2.5
Rationale: 0.75 g = 750 mg → 750 ÷ 500 = 1.5 mL.
44. The doctor orders 40 mg propranolol PO. Tablets: 10 mg each. How many tablets are needed?
A. 2
B. 3
C. 4 ✅
D. 5
Rationale: 40 ÷ 10 = 4 tablets.
45. Ordered: 0.5 g cefazolin IV. Available: 250 mg/mL. How many mL to give?
A. 1
B. 2 ✅
C. 3
D. 4
Rationale: 0.5 g = 500 mg → 500 ÷ 250 = 2 mL.
46. Doctor orders 0.4 g erythromycin. Suspension: 200 mg/5 mL. How many mL to give?
A. 5
B. 8
C. 10 ✅
D. 12
Rationale: 0.4 g = 400 mg → (400 × 5) ÷ 200 = 10 mL.
47. Ordered 100 mL IV fluid in 30 minutes. What is the infusion rate in mL/hr?
A. 100
B. 150
C. 200 ✅
D. 250
Rationale: 30 min = 0.5 hr → 100 ÷ 0.5 = 200 mL/hr.
48. Ordered: 0.2 mg clonidine. Tablets: 0.1 mg each. How many tablets will you give?
A. 1
B. 2 ✅
C. 3
D. 4
Rationale: 0.2 ÷ 0.1 = 2 tablets.
49. The doctor orders 2 mg midazolam IV. Vial reads 5 mg/mL. How many mL should be drawn?
A. 0.2
B. 0.3
C. 0.4 ✅
D. 0.5
Rationale: 2 ÷ 5 = 0.4 mL.
50. Ordered: 500 mg metronidazole IV in 100 mL D5W over 1 hour. What is the infusion rate?
A. 75 mL/hr
B. 100 mL/hr ✅
C. 125 mL/hr
D. 150 mL/hr
Rationale: 100 ÷ 1 = 100 mL/hr.
⚕️ NCLEX Fundamentals of Nursing MCQs
🩸 NCLEX Fluid & Electrolyte Questions
🧠 NCLEX Wound Care Practice Questions
🧾 Conclusion
Mastering medication calculation questions is essential for safe nursing practice and NCLEX success. Every nurse must confidently compute dosage conversions, IV flow rates, and pediatric calculations to avoid medication errors. Practice consistently with these 100+ NCLEX Medication Calculations Questions to build confidence and speed before your real exam.
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