FMGE 2026 - Pharmacology PYQs Practice Questions

Q: A 45-year-old man with a history of chronic alcoholism had been abstinent for the last 3 months while on de -addiction therapy. He consumed 60 mL of alcohol at a social gathering. Within 15–20 minutes, he developed nausea, vomiting, red rashes, throbbing headache, and palpitations. Which of the following drug was he most likely taking for alcohol dependence?

Disulfiram. ***Disulfiram*** - This drug acts by **inhibiting aldehyde dehydrogenase**, leading to the accumulation of **acetaldehyde** in the bloodstream when alcohol is consumed. - The resulting **disulfiram-ethanol reaction** presents with characteristic symptoms like facial flushing, throbbing headache, tachycardia, nausea, and vomiting within minutes of alcohol intake. *Chlorpromazine* - This is an **antipsychotic** medication used to manage psychiatric conditions and is not indicated for alcohol dependence. - It does not interfere with alcohol metabolism or cause the specific **acetaldehyde-mediated syndrome** described. *Fomepizole* - This drug is a **competitive inhibitor of alcohol dehydrogenase**, used specifically as an antidote for **methanol** and **ethylene glycol** toxicity. - It prevents the formation of toxic metabolites from these alcohols but does not produce a hypersensitivity reaction to ethanol. *TCA / Topiramate* - **Tricyclic antidepressants (TCAs)** are sometimes used for comorbid conditions but do not cause an adverse reaction to alcohol consumption. - **Topiramate** is used for alcohol cravings but works by modulating neurotransmitter receptors and does not cause a disulfiram-like reaction. [Practice more Pharmacology PYQs on OnCourse]

Q: Which of the following ECG change is most characteristically associated with lithium therapy?

T-wave inversion. ***T-wave inversion*** - **Lithium** therapy is well-recognized for causing benign and reversible ECG changes, most characteristically **T-wave flattening or inversion**. - These changes are generally considered **non-specific** and typically do not require discontinuation of the medication unless associated with clinical cardiac symptoms or toxicity. *ST-segment elevation* - **ST-segment elevation** is much more characteristic of conditions like **acute myocardial infarction** or **pericarditis**, not lithium use. - It is not a common side effect of mood stabilizers and would necessitate a thorough investigation for **ischemic heart disease**. *ST-segment depression* - **ST-segment depression** is a classic sign of **myocardial ischemia** or **digoxin toxicity**. - This finding is not associated with lithium therapy and would indicate a different underlying pathology requiring separate investigation. *QT interval prolongation* - While **QT interval prolongation** is a serious adverse effect of many antipsychotic medications and antidepressants, it is not the primary ECG change associated with **lithium**. - Prolongation of the **QT interval** poses a risk for **torsades de pointes**, and its absence is a distinguishing feature of lithium compared to many other psychotropic agents. [Practice more Pharmacology PYQs on OnCourse]

Question 1

A 45-year-old man with a history of chronic alcoholism had been abstinent for the last 3 months while on de -addiction therapy. He consumed 60 mL of alcohol at a social gathering. Within 15–20 minutes, he developed nausea, vomiting, red rashes, throbbing headache, and palpitations. Which of the following drug was he most likely taking for alcohol dependence?

Accepted Answer

Disulfiram

Answer

Chlorpromazine

Answer

Fomepizole

Answer

TCA / Topiramate

Question 2

A 28-year-old man develops descending flaccid paralysis, diplopia and dysphagia after eating improperly canned food. Another patient develops rapid paralysis after eating puffer fish. Which of the following correctly matches the mechanism of action?

Accepted Answer

Botulinum toxin blocks ACh release: Tetrodotoxin blocks voltage-gated sodium channels

Answer

Botulinum toxin blocks Na channels: Tetrodotoxin blocks ACh release

Answer

Botulinum toxin blocks nicotinic ACh receptors: Tetrodotoxin blocks Ca²⁺

Answer

Botulinum toxin increases ACh release: Tetrodotoxin blocks K⁺ channels

Question 3

A 26-year-old man diagnosed with diabetes insipidus was started on hydrochlorothiazide. The beneficial effect of hydrochlorothiazide in this patient is due to which of the following mechanisms?

Accepted Answer

Inhibition of Na+ reabsorption in DCT, leading to mild volume depletion and increased proximal water reabsorption

Answer

Direct stimulation of V2 receptors in the collecting duct

Answer

Blocking aquaporin -2 channels in the collecting duct

Answer

Increasing medullary interstitial osmolarity

Question 4

Which of the following ECG change is most characteristically associated with lithium therapy?

Accepted Answer

T-wave inversion

Answer

ST-segment elevation

Answer

ST-segment depression

Answer

QT interval prolongation

Question 5

Which of the following best describes the mechanism of action of gabapentin?

Accepted Answer

Blockage of the α2δ subunit of voltage -gated calcium channels

Answer

Sodium channel blockade

Answer

Opioid receptor blockade

Answer

NMDA receptor antagonism

Question 6

Which of the following best describes the mechanism of action of colchicine in acute attack of gout?

Accepted Answer

Inhibit migration of neutrophil chemotaxis

Answer

Inhibition of xanthine oxidase

Answer

Inhibition of cyclooxygenase (COX)

Answer

Blockade of IL-1 receptors

Question 7

A 65-year-old woman with breast cancer is receiving combination chemotherapy including methotrexate. To reduce toxicity, leucovorin is administered alongside methotrexate. Which of the following enzymes is bypassed by leucovorin rescue during methotrexa te therapy?

Accepted Answer

Dihydrofolate reductase

Answer

Thymidylate synthase

Answer

Dihydropteroate synthase

Answer

Purine nucleoside phosphorylase

Question 8

Which of the following best describes the mechanism of action of memantine when used for Alzheimer's disease?

Accepted Answer

NMDA receptor antagonist

Answer

Acetylcholinesterase inhibition

Answer

Blockade of A-beta amyloid

Answer

Dopamine D2 receptor antagonism

Question 9

What is the mechanism of action of finasteride?

Accepted Answer

5-alpha reductase inhibition

Answer

Adrenergic α1A receptor antagonism

Answer

Androgen receptor blockade

Answer

Phosphodiesterase inhibition

Question 10

A 45-year-old man with bronchial asthma is on regular theophylline therapy. He develops a fungal infection and is started on ketoconazole. After 4 –5 days, he presents with nausea, vomiting, tremors, palpitations, and restlessness. His serum theophylline level is found to be elevated. What is the most likely reason for this toxicity?

Accepted Answer

Ketoconazole inhibits CYP450 enzymes, decreasing theophylline metabolism

Answer

Ketoconazole induces CYP450 enzymes, increasing theophylline metabolism

Answer

Theophylline induces ketoconazole metabolism

Answer

Additive pharmacodynamic effect of both drugs

FMGE 2026 — Pharmacology