1|Page
NAPLEX (NORTH AMERICAN PHARMACIST
LICENSURE EXAMINATION) QUESTIONS
WITH VERIFIED SOLUTIONS AND
RATIONALES
1. A patient is prescribed 500 mg of a medication available as a 250 mg/5 mL oral
suspension. If the patient takes the medication twice daily, how many milliliters
should be dispensed for a 10-day supply?
A. 100 mL
B. 150 mL
C. 200 mL
D. 250 mL
Correct Answer: C
Rationale: The daily dose is 500 mg × 2 = 1,000 mg/day. The concentration is 250
mg/5 mL = 50 mg/mL. Daily volume = 1,000 mg ÷ 50 mg/mL = 20 mL/day. For 10
days: 20 mL × 10 = 200 mL .
2. A pharmacist needs to prepare 500 mL of a 10% dextrose solution using a 50%
dextrose stock solution and sterile water. How many milliliters of the 50%
,2|Page
dextrose stock solution are needed?
A. 50 mL
B. 75 mL
C. 100 mL
D. 125 mL
Correct Answer: C
Rationale: Using C₁V₁ = C₂V₂: (50%)(V₁) = (10%)(500 mL). V₁ = (10% × 500 mL) ÷ 50%
= 5,000 ÷ 50 = 100 mL .
3. A patient with a creatinine clearance of 30 mL/min is prescribed a medication
normally dosed at 500 mg every 12 hours. The package insert recommends a 50%
dose reduction for CrCl 10–50 mL/min. What is the appropriate daily dose for this
patient?
A. 250 mg/day
B. 500 mg/day
C. 750 mg/day
D. 1,000 mg/day
,3|Page
Correct Answer: B
Rationale: Normal daily dose = 500 mg × 2 = 1,000 mg/day. With 50% reduction:
1,000 mg × 0.5 = 500 mg/day .
4. What does the abbreviation "PO" mean on a prescription?
A. By mouth
B. Into the muscle
C. Under the skin
D. Into the vein
Correct Answer: A
Rationale: "PO" comes from the Latin per os, meaning "by mouth" .
5. Which route of administration provides the fastest systemic drug effect?
A. Oral
B. Topical
C. Intravenous
D. Rectal
, 4|Page
Correct Answer: C
Rationale: Intravenous administration delivers medication directly into the
bloodstream, bypassing absorption barriers .
6. Which branch of pharmacy studies how the body absorbs, distributes,
metabolizes, and eliminates drugs?
A. Pharmacodynamics
B. Pharmacokinetics
C. Medicinal chemistry
D. Pharmacognosy
Correct Answer: B
Rationale: Pharmacokinetics describes what the body does to a drug,
encompassing absorption, distribution, metabolism, and excretion .
7. Which organ is primarily responsible for drug metabolism?
A. Kidney
B. Liver
C. Stomach
D. Pancreas
NAPLEX (NORTH AMERICAN PHARMACIST
LICENSURE EXAMINATION) QUESTIONS
WITH VERIFIED SOLUTIONS AND
RATIONALES
1. A patient is prescribed 500 mg of a medication available as a 250 mg/5 mL oral
suspension. If the patient takes the medication twice daily, how many milliliters
should be dispensed for a 10-day supply?
A. 100 mL
B. 150 mL
C. 200 mL
D. 250 mL
Correct Answer: C
Rationale: The daily dose is 500 mg × 2 = 1,000 mg/day. The concentration is 250
mg/5 mL = 50 mg/mL. Daily volume = 1,000 mg ÷ 50 mg/mL = 20 mL/day. For 10
days: 20 mL × 10 = 200 mL .
2. A pharmacist needs to prepare 500 mL of a 10% dextrose solution using a 50%
dextrose stock solution and sterile water. How many milliliters of the 50%
,2|Page
dextrose stock solution are needed?
A. 50 mL
B. 75 mL
C. 100 mL
D. 125 mL
Correct Answer: C
Rationale: Using C₁V₁ = C₂V₂: (50%)(V₁) = (10%)(500 mL). V₁ = (10% × 500 mL) ÷ 50%
= 5,000 ÷ 50 = 100 mL .
3. A patient with a creatinine clearance of 30 mL/min is prescribed a medication
normally dosed at 500 mg every 12 hours. The package insert recommends a 50%
dose reduction for CrCl 10–50 mL/min. What is the appropriate daily dose for this
patient?
A. 250 mg/day
B. 500 mg/day
C. 750 mg/day
D. 1,000 mg/day
,3|Page
Correct Answer: B
Rationale: Normal daily dose = 500 mg × 2 = 1,000 mg/day. With 50% reduction:
1,000 mg × 0.5 = 500 mg/day .
4. What does the abbreviation "PO" mean on a prescription?
A. By mouth
B. Into the muscle
C. Under the skin
D. Into the vein
Correct Answer: A
Rationale: "PO" comes from the Latin per os, meaning "by mouth" .
5. Which route of administration provides the fastest systemic drug effect?
A. Oral
B. Topical
C. Intravenous
D. Rectal
, 4|Page
Correct Answer: C
Rationale: Intravenous administration delivers medication directly into the
bloodstream, bypassing absorption barriers .
6. Which branch of pharmacy studies how the body absorbs, distributes,
metabolizes, and eliminates drugs?
A. Pharmacodynamics
B. Pharmacokinetics
C. Medicinal chemistry
D. Pharmacognosy
Correct Answer: B
Rationale: Pharmacokinetics describes what the body does to a drug,
encompassing absorption, distribution, metabolism, and excretion .
7. Which organ is primarily responsible for drug metabolism?
A. Kidney
B. Liver
C. Stomach
D. Pancreas
