NCLEX Dosage Calculation Practice Questions (Part 1: 20 Items)
1. 1. Question
You are caring for a patient at home who must take magnesium
... [Show More] hydroxide/aluminum hydroxide (Maalox) 30 mL PO. How will you instruct the patient to measure the dose using ordinary household measuring devices? Fill in the blanks. Record your answer to the nearest whole number.
o Answer: (2) tbsp.
Incorrect
Correct answer:
• 2 tbsp.
Rationale:
• One tablespoon is equal to 15 mL.
• Convert 30 mL to tablespoons by multiplying it by one tablespoon.
• Then, divide 30 by 15 mL to get the final answer of 2 tbsp.
Computation:
2. 2. Question
A patient has a bottle of warfarin (Coumadin) 5 mg tablets at home. After his most recent international normalized ratio (INR), the doctor calls and tells him to take 7.5 mg/day. How many tablets (scored) should the patient take? Fill in the blanks and record your answer using one decimal place.
• Answer: (1.5) tablet(s)
Incorrect
Correct answer:
• 1.5 tablet
Formula:
Rationale:
• Use the standard formula above.
• First, multiply the desired dose (7.5 mg) to the vehicle (1 tablet) to get 7.5mg.
• Then, divide 7.5 mg by the drug on hand (5 mg) to get 1.5 tablets.
Computation:
3. 3. Question
You have an IVPB of ranitidine (Zantac) 50 mg in 50 mL D5W to run over 30 minutes. The tubing has a drip factor of 15. How many drops per minute will you set on the IV infusion controller? Fill in the blanks.
• Answer: (25) gtts/minute
Incorrect
Correct answer:
• 25 gtts/minute
Formula:
Rationale:
• Use the IV flow rate formula for gtts/minute above.
• Multiply 50 mL (total volume) to 15 gtts (drop factor) to get 750 gtts.
• Divide 750 gtts with 30 minutes (time in minutes) to get 25 gtts/minute.
Computation:
4. 4. Question
The physician orders alprazolam (Xanax) 0.5 mg PO. You have on hand Xanax 0.25 mg tablets. How many tablet(s) will you give? Fill in the blanks.
• Answer: (2) tablets(s)
Incorrect
Correct answer:
• 2 tablets
Formula:
Rationale:
• Use the standard formula above.
• Multiply 0.5 mg to 1 tablet (vehicle) to get 0.5 mg.
• Then divide 0.5 mg with 0.25 units (drug on hand) to get 2 tablets.
Computation:
5. 5. Question
You need to administer 250 mg of erythromycin (Erythrocin) PO. You have on hand 0.5 g tablets. How many tablet(s) will you give? Fill in the blanks.
• Answer: (1/2,0.5) tablet(s)
Incorrect
Correct answer:
• 1/2 tablet or 0.5 tablet
Formula:
Rationale:
• 1 g is equal to 1000 mg.
• Convert 250 mg to grams first by multiplying 250 mg to 1 g, then divide the answer by 1000 mg to get 0.25 g.
• Then use the standard formula above.
• Multiply 0.25 g (desired dose) to 1 tablet (vehicle) to get 0.25 g.
• Finally, divide 0.25 g by 0.5 g (drug on hand) to get 0.5 g or ½ tablet.
Computation:
6. 6. Question
You have available lorazepam (Ativan) 0.5 mg tablets, and you need to administer 1 mg PO. How many tablet(s) will you administer? Fill in the blanks.
• Answer: (2) tablet(s)
Incorrect
Correct answer:
• 2 tablets
Formula:
Rationale:
• Use the standard formula above.
• Multiply 1 mg (desired dose) to 1 tablet (vehicle) to get 1 mg.
• Then, divide 1 mg by 0.5 mg (drug on hand) to get 2 tablets.
Computation:
7. 7. Question
A patient with heart failure has a daily order for digoxin (Lanoxin) 0.25 mg PO. Digoxin 0.125 mg tablets are available. How many tablet(s) should you give? Fill in the blanks.
• Answer: (2) tablet(s)
Incorrect
Correct answer:
• 2 tablets
Formula:
Rationale:
• Use the standard formula above.
• Multiply 0.25 mg (desired dose) to 1 tablet (vehicle) to get 0.25 mg.
• Divide 0.25 mg by 0.125 mg (drug on hand) to get 2 tablets.
Computation:
8. 8. Question
The physician writes a “now” order for codeine 45 mg IM for a patient with a vertebral compression fracture. You have on hand codeine 60 mg/2 mL. How many milliliters should you give? Fill in the blanks and record your answer using one decimal place.
• Answer: (1.5) ml
Incorrect
Correct answer:
• 1.5 mL
Formula:
Rationale:
• Use the standard formula above.
• Multiply 45 mg (desired dose) to 2 mL (vehicle) to get 90 mL.
• Divide 90 mL by 60 mg (drug on hand) to get 1.5 mL.
Computation: [Show Less]