NCLEX: Drug Dosage Calculation Exam 9

Practice Mode – Questions and choices are randomly arranged, the answer is revealed instantly after each question, and there is no time limit for the exam.

Exam Mode – Questions and choices are randomly arranged, time limit of 1min per question, answers and grade will be revealed after finishing the exam.

Text Mode – Text version of the exam

1. You need to administer prochlorperazine (Compazine) 10 mg IM to a nauseated patient. You have on hand Compazine 5 mg/mL. How should you prepare the correct dose?

1. 5 mL
2. 2 mL
3. 1 mL
4. 0.5 mL

2. An order reads furosemide (Lasix) 40 mg IV push. You have on hand Lasix 20 mg/2 mL. How should you prepare the correct dose?

1. 4 mL
2. 2 mL
3. 1 mL
4. 0.5 mL

3. You need to administer 15 mg of morphine IM. It is supplied as gr 1/6 per mL. How should you prepare the correct dose?

1. 4.5 mL
2. 4 mL
3. 2 mL
4. 1.5 mL

4. You have on hand diazepam (Valium) 5 mg/mL. You need to administer 8 mg IV push stat. to a patient having a seizure. How much should you draw into the syringe?

1. 0.6 mL
2. 1 mL
3. 1.6 mL
4. 2 mL

5. A patient has an aminophylline IV drip ordered for acute asthma, to run at 20 mL/hour. No IV infusion controller is available right now. How many drops per minute will be required if microdrip tubing is used?

1. 30 gtts/min
2. 20 gtts/min
3. 15 gtts/min
4. 10 gtts/min

6. A safe maintenance dose of aminophylline is 0.36 mg/kg/hour. It is supplied as 100 mg/100 mL. Your patient is 130 pounds and is receiving 20 mL/hour. Is the dose safe?

1. patient is receiving 20 mg/hour; yes, dose is safe
2. patient is receiving 20 mg/hour; yes, dose is not safe
3. patient is receiving 40 mg/hour; yes, dose is safe
4. patient is receiving 40 mg/hour; yes, dose is not safe

7. Your patient is to receive metoprolol tartrate (Lopressor) 25 mg/day PO. The pharmacist dispenses 50 mg scored tablets. How many tablets should your patient take each day?

1. 1 tab
2. 1/2 tab
3. 2 tabs
4. 2 1/2 tabs

8. A patient has an IV piggyback of ceftriaxone (Rocephin) 500 mg in 50 mL D5W to run over 20 minutes. The tubing has a drip factor of 10. How many drops per minute should be administered?

1. 25 gtts/min
2. 20 gtts/min
3. 10 gtts/min
4. 4 gtts/min

9. A home care patient must restrict fluid intake to 2 L every 24 hours. He has only household measuring cups. How many cups may he drink daily and not exceed the 2 L limit?

1. 12 cups
2. 12.3 or 12 and 1/3 cups
3. 8 cups
4. 8.3 or 8 and 1/3 cups

10. A patient has an IV piggyback of ceftriaxone (Rocephin) 500 mg in 50 mL D5W to run over 20 minutes. If you use an IV infusion controller, how many milliliters per hour will you set?

1. 50 mL/hour
2. 150 mL/hour
3. 200 mL/hour
4. 17 mL/hour

Answers and Rationales

1. Answer: B. 10 mg x (1 mL/5 mg)= 2 mL
2. Answer: A. 40 mg x (2 mL/20 mg)= 4 mL
3. Answer: D. 15 mg x (1 gr/60 mg) x [ 1ml/ (1/6 gr) ]= 1.5 mL
4. Answer: C. 8 mg x (1 mL/5 mg)= 1.6 mL
5. Answer: B. (20 mL/1 hr) x (1 hr/ 60 mins) x (60 gtts/ mL)= 20 gtts/min
6. Answer: A. patient is receiving 20 mg/hour; yes, dose is safe
   • Because you have to compare a safe dose to the patient’s dose, you have to do two separate calculations:
     • (0.36 mg/kg) x (1 kg/ 2.2 lbs) x 130 lbs= 21.3 mg/hr is safe
     • (20 mL/hour) x (100 mg/100 mL)=  patient is receiving 20 mg/hr; yes, dose is safe.
7. Answer: B. 25 mg x (1 tab/ 50 mg)= 1/2 tab
8. Answer: A. (50 mL/20 mins) x (10 gtts/mL)= 25 gtts/min
9. Answer: D. 2L x (100 mL/1 L) x (1 cup/240 mL)= 8.3 or 8 and 1/3 cups
10. Answer: B. (50 mL/20 mins) x (60 mins/1 hr)= 150 mL/hour