Pharm.D. Doctor of Pharmacy Pharmaceutical Calculations and Compounding 1 — Questions and Answers
Question 1: A patient requires a 500 mg dose of amoxicillin. The available suspension is 250 mg/5 mL. How many mL should be dispensed per dose?
- 2.5 mL
- 5 mL
- 10 mL (Correct answer)
- 20 mL
Correct answer: 10 mL
Using the formula: (500 mg ÷ 250 mg) × 5 mL = 10 mL per dose.
Question 2: A prescription reads: acetaminophen 650 mg PO q6h PRN pain. What is the maximum daily dose?
- 1,950 mg
- 2,600 mg (Correct answer)
- 3,250 mg
- 4,000 mg
Correct answer: 2,600 mg
Dosing q6h means 4 doses per day; 650 mg × 4 = 2,600 mg per day.
Question 3: What does the Roman numeral 'XL' represent in a traditional prescription?
- 10
- 15
- 40 (Correct answer)
- 60
Correct answer: 40
In Roman numerals, XL represents 40 (50 minus 10), used in prescriptions to indicate quantity.
Question 4: How many grams of NaCl are needed to prepare 500 mL of a 0.9% w/v NaCl solution?
- 0.45 g
- 0.9 g
- 4.5 g (Correct answer)
- 9 g
Correct answer: 4.5 g
0.9% w/v = 0.9 g per 100 mL; for 500 mL: 0.9 × 5 = 4.5 g of NaCl.
Question 5: A patient weighs 154 lbs. A drug is dosed at 5 mg/kg. What is the total dose in mg?
- 350 mg (Correct answer)
- 385 mg
- 700 mg
- 770 mg
Correct answer: 350 mg
154 lbs ÷ 2.2 = 70 kg; 70 kg × 5 mg/kg = 350 mg.
Question 6: An IV fluid is running at 125 mL/hr. How many hours will a 1-liter bag last?
- 6 hours
- 8 hours (Correct answer)
- 10 hours
- 12 hours
Correct answer: 8 hours
1,000 mL ÷ 125 mL/hr = 8 hours for the 1-liter bag to infuse.
Pharm.D. Doctor of Pharmacy Pharmaceutical Calculations and Compounding 1
A patient requires a 500 mg dose of amoxicillin.
The available suspension is 250 mg/5 mL.
How many mL should be dispensed per dose?