UPSC-CMS 2025 - Pharmacology Practice Questions

Q: Which one of the following is used to reverse the anticoagulant effects of Dabigatran?

Idarucizumab. ***Idarucizumab*** - **Idarucizumab** is a **monoclonal antibody fragment** specifically designed to bind to dabigatran and its active metabolites. - This binding neutralizes the anticoagulant effect of dabigatran, providing **rapid reversal** in emergency situations. *Desferrioxamine* - **Desferrioxamine** is a **chelating agent** used to treat **iron poisoning**. - It works by binding to iron in the bloodstream, facilitating its excretion from the body, and has no effect on anticoagulant drugs. *Protamine* - **Protamine** is used to reverse the anticoagulant effects of **heparin** by forming a stable salt with it. - It is **not effective** for reversing the effects of direct oral anticoagulants like dabigatran. *Glucarpidase* - **Glucarpidase** is an enzyme used to reduce toxic plasma methotrexate concentrations in patients with impaired renal function. - It catalyzes the hydrolysis of methotrexate into inactive metabolites and has **no role** in anticoagulant reversal.

Q: Fomepizole is an antidote used to treat poisoning from which of the following substances? I. Methanol II. Digoxin III. Cocaine IV. Ethylene glycol Select the correct answer using the code given below :

I and IV. ***I and IV*** - **Fomepizole** is a competitive inhibitor of **alcohol dehydrogenase**, the enzyme that metabolizes both methanol and ethylene glycol into toxic metabolites [1]. - For **methanol** poisoning: Prevents conversion to **formic acid**, which causes metabolic acidosis and optic nerve damage [2]. - For **ethylene glycol** poisoning: Prevents conversion to **glycolic acid and oxalic acid**, which cause metabolic acidosis, renal failure, and calcium oxalate crystal deposition [1]. - Fomepizole is the preferred antidote over ethanol due to its safer profile and ease of administration. *III and IV* - While ethylene glycol (IV) is correctly identified, **cocaine** (III) poisoning is not treated with fomepizole. - Cocaine toxicity management involves supportive care, benzodiazepines for agitation and seizures, and management of cardiovascular complications (hypertension, arrhythmias). - Fomepizole has no role in cocaine overdose as the toxic mechanism does not involve alcohol dehydrogenase. *I and II* - While methanol (I) is correctly identified, **digoxin** (II) poisoning is not treated with fomepizole. - Digoxin toxicity is managed with **digoxin-specific antibody fragments (Digoxin Fab)**, which bind and neutralize digoxin. - Fomepizole's mechanism of alcohol dehydrogenase inhibition is irrelevant to digoxin toxicity. *II and III* - Neither **digoxin** (II) nor **cocaine** (III) poisoning is treated with fomepizole. - Both substances have different toxic mechanisms unrelated to alcohol dehydrogenase. - Digoxin requires Fab fragments; cocaine requires supportive care and symptomatic management.

Q: What is the antidote for belladonna poisoning?

Physostigmine. ***Physostigmine*** - **Physostigmine** is a **reversible acetylcholinesterase inhibitor** that increases acetylcholine levels at the muscarinic and nicotinic receptors. - This effectively counteracts the **anticholinergic effects** of belladonna, which contains atropine and scopolamine, by overcoming the competitive blockade. *Atropine* - **Atropine** is the primary toxic component in belladonna, acting as a **muscarinic acetylcholine receptor antagonist**. - Administering atropine would worsen the existing anticholinergic toxidrome, making it a contraindicated treatment. *Amitriptyline* - **Amitriptyline** is a **tricyclic antidepressant** and has significant **anticholinergic properties** itself. - Using amitriptyline would exacerbate rather than treat the symptoms of belladonna poisoning due to its similar mechanism of action. *Flumazenil* - **Flumazenil** is an **antagonist of benzodiazepine receptors** and is used to reverse benzodiazepine overdose. - It has no effect on the muscarinic receptor blockade caused by belladonna alkaloids and would not be effective in this poisoning.

Q: Which one of the following prevents gastrointestinal absorption of thallium?

Prussian blue. ***Prussian blue*** - **Prussian blue** (ferric hexacyanoferrate) acts as an ion exchanger in the gastrointestinal tract, binding to thallium and preventing its absorption. - This complex of thallium and Prussian blue is then **excreted in the feces**, reducing systemic toxicity. *Calcium carbonate* - **Calcium carbonate** is an antacid primarily used to neutralize stomach acid or as a calcium supplement. - It does not specifically bind to or prevent the absorption of **thallium**. *Potassium permanganate* - **Potassium permanganate** is a strong oxidizing agent sometimes used for gastric lavage in certain poisonings. - It does not form a stable, non-absorbable complex with **thallium** to prevent its gastrointestinal uptake. *Penicillamine* - **Penicillamine** is a chelating agent used for heavy metal poisoning, such as copper (in Wilson's disease) or lead. - While it can chelate some metals, its primary mechanism involves forming soluble complexes that are excreted renally, rather than directly preventing **gastrointestinal absorption** of thallium.

Q: A 45 year old farmer came with accidental consumption of a pesticide. He complained of frequent urination and excessive salivation. Which one of the following toxidromes is most likely to be associated with this poisoning?

Cholinergic. ***Cholinergic*** The patient's symptoms of frequent urination and excessive salivation, along with accidental pesticide consumption, are classic signs of **organophosphate poisoning**, which falls under the **cholinergic toxidrome** [1, 2]. This toxidrome is characterized by excessive stimulation of the **cholinergic system**, leading to symptoms memorized by the acronyms **SLUDGE** (Salivation, Lacrimation, Urination, Defecation, Gastrointestinal upset, Emesis) and **DUMBBELS** (Diarrhea, Urination, Miosis, Bradycardia, Bronchorrhea, Emesis, Lacrimation, Salivation) [1]. *Adrenergic* The adrenergic toxidrome is associated with sympathetic overactivity, leading to symptoms like **tachycardia**, **hypertension**, **mydriasis**, agitation, and hyperthermia. These symptoms are opposite to the parasympathetic overactivity observed in this patient. *Hypnotic* The hypnotic toxidrome typically presents with **CNS depression**, including **sedation**, **respiratory depression**, **bradycardia**, and **hypotension**. This toxidrome does not match the patient's symptoms of excessive salivation and frequent urination. *Serotonergic* The serotonergic toxidrome (serotonin syndrome) is characterized by a triad of mental status changes, autonomic hyperactivity (e.g., **tachycardia**, **hypertension**, hyperthermia), and neuromuscular abnormalities (e.g., **hyperreflexia**, clonus). The patient's presentation does not align with these hallmark features.

Q: Consider the following regarding salicylate poisoning : I. Arterial pH of 7.25 , anion gap of 18 mmol / L II. Arterial pH of 7.25 , anion gap of 10 mmol / L III. pCO2 of 20 mm Hg IV. pCO2 of 48 mm Hg Which disturbance is likely to be encountered?

I and III. ***I and III*** - Salicylate poisoning typically presents with a **mixed acid-base disorder** consisting of primary **respiratory alkalosis** and primary **metabolic acidosis with an increased anion gap** [1]. - A pH of 7.25 with an anion gap of 18 mmol/L (normal range 8-12 mmol/L) indicates **metabolic acidosis with an increased anion gap**, while a pCO2 of 20 mmHg (normal range 35-45 mmHg) indicates **respiratory alkalosis** [2]. *II and III* - An anion gap of 10 mmol/L is within the normal range, which is inconsistent with the **metabolic acidosis with increased anion gap** expected in salicylate poisoning [1]. - While pCO2 of 20 mmHg indicates respiratory alkalosis, the normal anion gap makes this combination less likely for salicylate poisoning. *II and IV* - An anion gap of 10 mmol/L is within the normal range, which does not reflect the typical **anion gap metabolic acidosis** seen in salicylate poisoning. - A pCO2 of 48 mmHg indicates respiratory acidosis, which is generally not the primary respiratory disturbance in salicylate poisoning; rather, **respiratory alkalosis** due to direct stimulation of the respiratory center is more characteristic [1]. *I and IV* - While an anion gap of 18 mmol/L is consistent with **anion gap metabolic acidosis**, a pCO2 of 48 mmHg indicates respiratory acidosis. - The classic picture of salicylate poisoning includes **respiratory alkalosis** due to direct stimulation of the respiratory center, not respiratory acidosis [1].

Q: Which one of the following groups of drugs is ineffective against gram positive bacteria?

Monobactams. Monobactams - **Monobactams**, such as **aztreonam**, have a narrow spectrum of activity primarily targeting aerobic **Gram-negative bacteria** [1]. - They lack significant activity against **Gram-positive organisms** and **anaerobes** due to differences in cell wall structure and penicillin-binding proteins (PBPs) [1]. *Glycopeptides* - **Glycopeptides**, like **vancomycin**, are highly effective against a wide range of **Gram-positive bacteria**, including **MRSA** (methicillin-resistant *Staphylococcus aureus*) [3]. - They inhibit cell wall synthesis by binding to the D-Ala-D-Ala precursor, which is crucial for **Gram-positive cell wall integrity**. *Fluoroquinolones* - **Fluoroquinolones** are broad-spectrum antibiotics with activity against both **Gram-positive** and **Gram-negative bacteria** [4]. - While some newer agents (*e.g., levofloxacin, moxifloxacin*) have enhanced **Gram-positive coverage**, older agents (e.g., **ciprofloxacin**) are less potent against Gram-positives [4]. *First generation cephalosporins* - **First-generation cephalosporins** (e.g., **cefazolin**, **cephalexin**) exhibit good activity against many **Gram-positive bacteria**, including **staphylococci** and **streptococci** [2]. - They are commonly used for infections caused by **Gram-positive organisms** and as surgical prophylaxis [2].

Q: Consider the following statements with regard to the treatment of vitamin A deficiency : I. Repeated high doses of retinol can cause liver damage and teratogenicity II. Acute overdose of vitamin A may lead to increased intracranial pressure and skin desquamation III. Regular vitamin A supplementation is also recommended for pregnant women even in countries where vitamin A deficiency is not endemic IV. Excessive intake of carotene may cause harmless orange pigmentation of the skin Which of the statements given above are correct?

I, II and IV. **I, II and IV** - Statement I is correct: Repeated high doses of **retinol** (preformed vitamin A) can accumulate in the liver, leading to **hepatotoxicity** and potential **teratogenic effects** on a developing fetus. - Statement II is correct: **Acute vitamin A overdose** can manifest as symptoms such as **increased intracranial pressure** (pseudotumor cerebri) and **skin desquamation** (peeling skin). - Statement IV is correct: Excessive intake of **carotene** (a vitamin A precursor from plants) can cause **carotenemia**, characterized by a harmless **orange pigmentation** of the skin, but it does not lead to vitamin A toxicity due to regulated conversion. *II, III and IV* - This option incorrectly includes statement III, which is false because regular vitamin A supplementation is generally **not recommended for pregnant women in non-endemic areas** due to the risk of teratogenicity. - The other statements (II and IV) are correct, as acute overdose of vitamin A can cause increased intracranial pressure and skin desquamation, and excessive carotene intake can lead to harmless orange skin pigmentation. *I, II and III* - This option incorrectly includes statement III, which is false as routine vitamin A supplementation is **contraindicated for pregnant women in non-endemic areas** due to the risk of birth defects. - Statements I and II are correct, as high retinol doses can cause liver damage and teratogenicity, and acute vitamin A overdose can lead to increased intracranial pressure and skin desquamation. *I, III and IV* - This option incorrectly includes statement III, which is false because **pregnant women in non-endemic areas should avoid regular vitamin A supplementation** to prevent toxicity and teratogenic effects. - Statements I and IV are correct; high retinol doses can cause liver damage and teratogenicity, and excessive carotene intake can result in harmless orange skin pigmentation.

Q: Which one of the following oral drugs may be used as adjunctive therapy in the management of super-refractory status epilepticus?

Topiramate. ***Topiramate*** - **Topiramate** is an antiepileptic drug with multiple mechanisms of action, including potentiation of **GABAergic** activity, blockade of **voltage-gated sodium channels**, and antagonism of **AMPA/kainate glutamate receptors**. - Its broad-spectrum action and ability to be administered orally make it a suitable **adjunctive therapy** in complex cases like **super-refractory status epilepticus (SRSE)**, where patients have failed other conventional treatments. *Clobazam* - **Clobazam** is a **benzodiazepine** primarily used as an **anxiolytic** and antiepileptic drug, particularly for Lennox-Gastaut syndrome. - While supportive in status epilepticus, its primary role is in acute seizure termination rather than as a long-term adjunctive therapy for **super-refractory status epilepticus** post-acute phase. *Clonazepam* - **Clonazepam** is another **benzodiazepine** with potent **antiepileptic** properties. - It is effective in terminating acute seizures but is not typically used as a primary oral adjunctive agent for **super-refractory status epilepticus** due to its sedative side effects and potential for tolerance. *Lamotrigine* - **Lamotrigine** is an **antiepileptic drug** that primarily works by inhibiting **voltage-sensitive sodium channels**, thereby stabilizing neuronal membranes and modulating the release of excitatory neurotransmitters. - While effective for various seizure types, including focal and generalized seizures, it is not a first-line or common choice as an **adjunctive oral therapy** in **super-refractory status epilepticus**, which often requires drugs with faster onset or broader mechanisms beyond sodium channel blockade.

Q: Which of the following statements are correct regarding the use of benzodiazepines in the initial management of status epilepticus? I. Upto two doses may be used 5 minutes apart, if seizures are not controlled II. For Lorazepam, only a single dose should be used, even if seizures are not controlled III. Dose of midazolam at this stage is 1-15 mcg / kg / min infusion IV. Dose of both lorazepam and midazolam is 0.1 mg / kg Select the answer using the code given below :

I and IV. ***I and IV*** - According to current guidelines, **up to two doses** of a benzodiazepine may be administered 5 minutes apart if the **seizures are not controlled** after the initial dose. - The recommended dose for both **lorazepam and midazolam** in the initial management of status epilepticus is **0.1 mg/kg**. *II and IV* - This option is incorrect because statement II is false, as **multiple doses of lorazepam** can be administered if seizures are not controlled. - While statement IV is correct regarding the dosage of lorazepam and midazolam. *I and III* - This option is incorrect because statement III is false, as **1-15 mcg/kg/min infusion** is the dose for **continuous infusion** of midazolam in refractory status epilepticus, not the initial bolus dose. - Statement I is correct but paired with an incorrect statement. *II and III* - This option is incorrect because both statements II and III are false regarding the initial management of status epilepticus. - As previously stated, **multiple doses of lorazepam** can be used, and the given midazolam dose is for **continuous infusion**, not the initial bolus.

Question 1

Which one of the following is used to reverse the anticoagulant effects of Dabigatran?

Accepted Answer

Idarucizumab

Answer

Desferrioxamine

Answer

Protamine

Answer

Glucarpidase

Question 2

Fomepizole is an antidote used to treat poisoning from which of the following substances?
I. Methanol
II. Digoxin
III. Cocaine
IV. Ethylene glycol

Select the correct answer using the code given below :

Accepted Answer

I and IV

Answer

III and IV

Answer

I and II

Answer

II and III

Question 3

What is the antidote for belladonna poisoning?

Accepted Answer

Physostigmine

Answer

Atropine

Answer

Amitriptyline

Answer

Flumazenil

Question 4

Which one of the following prevents gastrointestinal absorption of thallium?

Accepted Answer

Prussian blue

Answer

Calcium carbonate

Answer

Potassium permanganate

Answer

Penicillamine

Question 5

A 45 year old farmer came with accidental consumption of a pesticide. He complained of frequent urination and excessive salivation. Which one of the following toxidromes is most likely to be associated with this poisoning?

Accepted Answer

Cholinergic

Answer

Adrenergic

Answer

Hypnotic

Answer

Serotonergic

Question 6

Consider the following regarding salicylate poisoning :
I. Arterial pH of 7.25 , anion gap of 18 mmol / L
II. Arterial pH of 7.25 , anion gap of 10 mmol / L
III. pCO2 of 20 mm Hg
IV. pCO2 of 48 mm Hg

Which disturbance is likely to be encountered?

Accepted Answer

I and III

Answer

II and III

Answer

II and IV

Answer

I and IV

Question 7

Which one of the following groups of drugs is ineffective against gram positive bacteria?

Accepted Answer

Monobactams

Answer

Glycopeptides

Answer

Fluoroquinolones

Answer

First generation cephalosporins

Question 8

Consider the following statements with regard to the treatment of vitamin A deficiency :
I. Repeated high doses of retinol can cause liver damage and teratogenicity
II. Acute overdose of vitamin A may lead to increased intracranial pressure and skin desquamation
III. Regular vitamin A supplementation is also recommended for pregnant women even in countries where vitamin A deficiency is not endemic
IV. Excessive intake of carotene may cause harmless orange pigmentation of the skin

Which of the statements given above are correct?

Accepted Answer

I, II and IV

Answer

II, III and IV

Answer

I, II and III

Answer

I, III and IV

Question 9

Which one of the following oral drugs may be used as adjunctive therapy in the management of super-refractory status epilepticus?

Accepted Answer

Topiramate

Answer

Clobazam

Answer

Clonazepam

Answer

Lamotrigine

Question 10

Which of the following statements are correct regarding the use of benzodiazepines in the initial management of status epilepticus?
I. Upto two doses may be used 5 minutes apart, if seizures are not controlled
II. For Lorazepam, only a single dose should be used, even if seizures are not controlled
III. Dose of midazolam at this stage is 1-15 mcg / kg / min infusion
IV. Dose of both lorazepam and midazolam is 0.1 mg / kg

Select the answer using the code given below :

Accepted Answer

I and IV

Answer

II and IV

Answer

I and III

Answer

II and III

UPSC-CMS 2025 — Pharmacology