NAPLEX QBANK Drug Interactions and Adverse Effects

Question 1

A patient stabilized on an SSRI is prescribed tramadol for acute pain. Which serious adverse reaction is most likely to result from this combination?

Accepted Answer

Serotonin syndrome

Answer

Neuroleptic malignant syndrome

Answer

Anticholinergic toxicity

Answer

Extrapyramidal effects

Question 2

A patient stabilized on warfarin begins amiodarone therapy for atrial fibrillation. What dose adjustment to warfarin is typically required?

Accepted Answer

Decrease warfarin dose by 30–50%

Answer

Increase warfarin dose by 50%

Answer

No dose adjustment is needed

Answer

Discontinue warfarin immediately

Question 3

Which antibiotic class most significantly inhibits CYP3A4 and increases the risk of statin-induced rhabdomyolysis?

Accepted Answer

Macrolides

Answer

Fluoroquinolones

Answer

Tetracyclines

Answer

Sulfonamides

Question 4

What is the primary mechanism by which NSAIDs increase the toxicity of low-dose methotrexate?

Accepted Answer

Competing with methotrexate for renal tubular secretion

Answer

Inducing methotrexate hepatic metabolism

Answer

Displacing methotrexate from plasma protein binding sites

Answer

Increasing GI absorption of methotrexate

Question 5

Which drug combination is most likely responsible for a patient developing a prolonged QTc interval on ECG?

Accepted Answer

Azithromycin and haloperidol

Answer

Metoprolol and lisinopril

Answer

Metformin and glipizide

Answer

Amlodipine and atorvastatin

Question 6

A patient maintained on lithium for bipolar disorder begins taking ibuprofen regularly for arthritis pain. What effect on lithium levels is expected?

Accepted Answer

Lithium levels will increase

Answer

Lithium levels will decrease

Answer

Lithium levels will remain unchanged

Answer

Lithium half-life will shorten significantly

Question 7

Which adverse effect is characteristic of ACE inhibitors but is NOT shared by angiotensin receptor blockers (ARBs)?

Accepted Answer

Dry, persistent cough

Answer

Hyperkalemia

Answer

First-dose hypotension

Answer

Renal impairment