Questions for the NAPLEX were updated on : Nov 21 ,2025
Which of these is an example of postrenal acute kidney injury (AKI)?
A
Explanation:
Benign prostatic hyperplasia (BPH) is an example of postrenal acute kidney injury (AKI). Postrenal
AKI, as the name suggests, involves an effect ‘post’ or ‘beyond’ the kidney, to problems that emerge
downstream from the kidney. BPH is one such example of that. Other examples include kidney
stones, bladder stones and bladder cancer.
What is the active ingredient of the medicine Lyrica?
D
Explanation:
Pregabalin is the active ingredient of the medicine Lyrica; a drug used to treat epilepsy, neuropathic
pain, fibromyalgia and generalized anxiety disorder (GAD).
Before use, which of the following products should be used to clean surfaces of a laminar flow hood?
B
Explanation:
Before each use, 70% isopropyl alcohol should be used to clean surfaces of a laminar flow hood.
A 49-year-old’s blood test results have come back from the lab. Their chloride level currently
measures 99 mEq/L. How should you interpret this result?
C
Explanation:
Serum chloride levels should ideally fall between 96-106 mEq/L. For this reason, the patient’s
chloride level has come back as normal.
How many millimoles of sodium are in 0.9% sodium chloride?
D
Explanation:
0.9% = 9 grams per every 1,000mL Molecular weight of NaCl = 58.5 9 / 58.5 = 0.154 moles 0.154
moles is the same as 154 millimoles There are 154 millimoles of sodium ions and 154 millimoles of
chloride ions in 0.9% sodium chloride.
A 51-year-old patient, who takes a calcium channel blocker (CCB), reports that he is experiencing
constipation. Which CCB is the patient most likely to be taking?
C
Explanation:
Non-dihydropyridine calcium channel blockers – which are diltiazem and verapamil – are statistically
more likely to cause constipation. Of these two, verapamil has a higher probability of causing this
side effect.
The administration of dapsone gel for the topical treatment of acne vulgaris in patients with G6PD
deficiency may produce which of these?
A. Anaphylaxis
B. Fungal infections
C. Hemolysis
D. Immunosuppression
C
(none)
Explanation
Explanation:
Dapsone treatment has produced dose-related hemolysis and hemolytic anemia. Individuals with
glucose-6¬ phosphate dehydrogenase (G6PD) deficiency are more prone to hemolysis.
A patient presents in the pharmacy in a delirious state with pinpoint pupils. Which of the following
toxicity states does the patient most likely have?
B
Explanation:
Signs of opioid overdose include pinpoint pupils, delirious state, nausea / vomiting, respiratory
depression and sleepiness or loss of consciousness. Naloxone may be used to reverse the effects of
opioid overdose.
Which H2-receptor blocker may cause gynecomastia in men due to its antiandrogenic effects?
C
Explanation:
Cimetidine has multiple drug interactions due to its inhibitory effects on CYP1A2, 2C9, 2D6, and 3A4.
Inhibition of these enzymes can cause an increase in the serum concentrations of drugs metabolized
by these enzymes, leading to toxicity.
Which of these medicines is well-known to cause a positive direct Coombs test?
A. Methyldopa
B. Labetalol
C. Hydralazine
D. Nifedipine
A
(none)
Explanation
Explanation:
The direct Coombs test is used to test for autoimmune hemolyticanemia – a condition in which the
body attacks red blood cells, leading to anemia. Some drugs can cause a positive direct Coombs test
– methyldopa being one of the most well-known (via IgG-mediated type II hypersensitivity reaction).
Other drugs that can cause this effect include quinidine (IgM-mediated activation) and penicillins (at
very high doses).
In the management of acute ischemic stroke, within how many minutes from symptom onset should
alteplase be administered?
A
Explanation:
In the management of acute ischemic stroke, alteplase should be administered within 3 hours of
symptom onset.
What is the active ingredient found in the medicine Adalat?
A
Explanation:
The dihydropyridine drug – nifedipine – is the active ingredient found in the medicine Adalat.
Nifedipine is used to treat angina, Reynaud’s phenomenon and hypertension. It is also used as a
tocolytic agent in premature labor.
What is the amount of potassium permanganate in 300mL of a 1 in 25 solution?
C
Explanation:
We have 1g of potassium permanganate in 25mL We have 300mL of solution
For every 25mL of that 300mL, we have 1g of KmnO4
300mL must have 12g of potassium permanganate (300ml/25mL)
Mesna is typically administered alongside which of these chemotherapeutic agents?
C
Explanation:
Mesna is administered to patients taking either ifosfamide or cyclophoshamide to conjugate toxic
acrolein and therefore prevent hemorrhagic cystitis (bladder bleeding).
What is the mechanism of action of the active ingredient found in Zyflo?
B
Explanation:
Zileuton is the active ingredient found in the medicine Zyflo; a medicine that works as a 5-
lipoxygenase inhibitor. As such, zileuton inhibits leukotrienes (LTB4, LTC4, LTD4, and LTE4) formation,
and is used for the maintenance treatment of asthma in patients older than the age of 12. In 2
percent of patients, it raises liver enzymes. Sinusitis and nausea are the most common side effects.