INI-CET 2025 - Pharmacology PYQs Practice Questions

Q: Sodium thiopentone is regarded as an ultrashort-acting drug due to

Rapid redistribution. ***Rapid redistribution*** - The ultrashort action of **thiopentone** is primarily due to its rapid **redistribution** from the central compartment (brain) to peripheral tissues (muscle and fat). - This rapid drop in plasma and brain concentration leads to swift termination of the drug's hypnotic effect. *Metabolism* - While thiopentone is metabolized primarily by the **liver**, its metabolic clearance is relatively slow, contributing to its long elimination half-life rather than its quick onset/offset. *Excretion* - Thiopentone is only minimally excreted unchanged by the **kidneys**; renal excretion is not the reason for the ultrashort duration of action. *Short elimination half-life* - Thiopentone actually has a **long elimination half-life** (around 10–12 hours) because of its high lipid solubility, long protein binding, and slow systemic metabolism. - The duration of action is governed by redistribution, not by the elimination half-life. [Practice more Pharmacology PYQs on OnCourse]

Q: Which of the following psychoactive substances is a new, rapidly acting antidepressant?

Ketamine. ***Ketamine*** - It is an **NMDA receptor antagonist** that produces a rapid and often sustained antidepressant effect, typically within hours, making it a new class of rapidly acting antidepressants. - **Esketamine** (a derivative) is specifically approved for **treatment-resistant depression** and acute suicidal ideation. *Bupropion* - This is a traditional antidepressant classified as a **Norepinephrine and Dopamine Reuptake Inhibitor (NDRI)**. - Like most conventional antidepressants (SSRIs, SNRIs), Bupropion has a **delayed onset of action**, usually requiring weeks for clinical efficacy. *Haloperidol* - This substance is a typical or first-generation **antipsychotic** used primarily to treat conditions involving psychosis, such as schizophrenia and acute mania. - Its primary function involves potent blockade of **Dopamine D2 receptors**, and it is not used in the management of primary depression. *Cannabinoids* - These agents primarily modulate the **endocannabinoid system (CB1 and CB2 receptors)**, and while they have CNS effects, they are generally not used as primary, rapid-acting antidepressants. - Research into cannabinoids for mood is complex, and they may sometimes lead to dysphoria or **anxiety/psychosis exacerbation**. [Practice more Pharmacology PYQs on OnCourse]

Q: Imipramine and Diphenhydramine are given together to a patient. Why is this combination considered irrational?

Both have anticholinergic action. ***Both have anticholinergic action*** - Imipramine, being a **Tricyclic Antidepressant (TCA)**, possesses significant **anticholinergic properties** (Muscarinic receptor blockade). - Diphenhydramine, a first-generation antihistamine, is also a highly effective **anticholinergic agent**; their co-administration leads to severe, potentially fatal, additive anticholinergic effects (e.g., acute confusion, severe urinary retention, paralytic ileus). *Both cause serotonin syndrome* - While Imipramine is a weak **Serotonin-Norepinephrine Reuptake Inhibitor (SNRI)**, Diphenhydramine does not directly contribute significantly to **serotonin toxicity**. - The primary and most hazardous interaction is the severe risk of **anticholinergic crisis**, not Serotonin Syndrome. *Both cause hypotension* - Imipramine can cause **orthostatic hypotension** due to its **alpha-1 adrenergic blockade** effects. - Although side effects include hypotension, the combined risk of severe **anticholinergic side effects** (delirium, ileus) is the overwhelming reason this combination is irrational. *Both cause increased sedation* - Both drugs are highly sedating, which is a valid concern for driving and daily function, mediated by **H1 receptor antagonism**. - However, while increased sedation is a risk, the combination is specifically deemed irrational because of the risk of life-threatening **anticholinergic toxicity**, which is a more critical pharmacological interaction than simple additive sedation. [Practice more Pharmacology PYQs on OnCourse]

Q: Which of the following statements regarding Thalidomide is correct? a. It acts as an antimetabolite and is useful as an immunosuppressant b. It is used in the treatment of multiple myeloma c. It is used in the management of Type 2 lepra reaction (ENL) d. It is teratogenic

b, c, d. ***b, c, d*** - Statements b, c, and d are correct: Thalidomide is an **Immunomodulatory Drug (IMiD)** used effectively in the treatment of **multiple myeloma**, it is the drug of choice for **Erythema Nodosum Leprosum (ENL)** (Type 2 lepra reaction), and it is historically significant for causing **phocomelia** (teratogenicity). - Its mechanism involves downregulation of **pro-inflammatory cytokines** like TNF-alpha, which underlies its use in ENL, and anti-angiogenic/anti-proliferative effects against myeloma cells. *a, b, c* - Statement 'a' is incorrect because Thalidomide is an **Immunomodulatory Drug (IMiD)**, not an **antimetabolite** (a class of drugs that inhibit DNA/RNA synthesis). - Inclusion of the incorrect mechanism ('a') invalidates this set, despite 'b' (multiple myeloma) and 'c' (ENL) being correct clinical applications. *a, c, d* - This combination is incorrect primarily because it includes statement 'a', which wrongly defines Thalidomide as an **antimetabolite**. - Crucially, this option omits statement 'b', which is a major, current indication for Thalidomide in **multiple myeloma**. *a, b, d* - This combination wrongly includes the factual error of statement 'a' (it is not an **antimetabolite**). - It also misses statement 'c', which is the prominent use of Thalidomide in **Type 2 lepra reaction (ENL)**. [Practice more Pharmacology PYQs on OnCourse]

Q: According to the Drugs and Cosmetics Rules, match the following medications with their corresponding schedules: 1. Insulin, 2. Hepatitis B vaccine, 3. Morphine, 4. Veterinary drugs. Schedules: A. Schedule H, B. Schedule Z, C. Schedule G, D. Schedule X.

1-C, 2-A, 3-D, 4-B. ***1-C, 2-A, 3-D, 4-B*** - **Insulin** (1) is properly categorized under **Schedule G** (C), specifying drugs that must be taken only under the supervision of a registered medical practitioner. - The **Hepatitis B vaccine** (2) falls under **Schedule H** (A - general prescription drugs), **Morphine** (3) is correctly placed under **Schedule X** (D - narcotics/psychotropics), and **Veterinary drugs** (4) are covered by **Schedule Z** (B - proprietary veterinary medicines). *1-C, 2-D, 3-B, 4-A* - This option incorrectly assigns the **Hepatitis B vaccine** (2) to Schedule D (which deals with standards of imported drugs) instead of Schedule H. - It incorrectly places **Morphine** (3) under Schedule B (fees for tests and analysis) instead of the appropriate Schedule X. *1-B, 2-A, 3-D, 4-C* - This option incorrectly assigns **Insulin** (1) to Schedule B (fees for test or analysis by the Central Drugs Laboratory) instead of Schedule G. - It incorrectly places **Veterinary drugs** (4) under Schedule C (which deals with biological products intended for parenteral administration). *1-D, 2-B, 3-A, 4-C* - This option incorrectly assigns **Insulin** (1) to Schedule D (rules regarding the importation of drugs) and **Morphine** (3) to Schedule A (forms of application for licenses). - It also incorrectly links the **Hepatitis B vaccine** (2) to Schedule B (fees for tests rather than a drug category). [Practice more Pharmacology PYQs on OnCourse]

Question 1

Sodium thiopentone is regarded as an ultrashort-acting drug due to

Accepted Answer

Rapid redistribution

Answer

Short elimination half-life

Answer

Metabolism

Answer

Excretion

Question 2

Which of the following psychoactive substances is a new, rapidly acting antidepressant?

Accepted Answer

Ketamine

Answer

Bupropion

Answer

Haloperidol

Answer

Cannabinoids

Question 3

Imipramine and Diphenhydramine are given together to a patient. Why is this combination considered irrational?

Accepted Answer

Both have anticholinergic action

Answer

Both cause serotonin syndrome

Answer

Both cause hypotension

Answer

Both cause increased sedation

Question 4

Which of the following statements regarding Thalidomide is correct?
a. It acts as an antimetabolite and is useful as an immunosuppressant
b. It is used in the treatment of multiple myeloma
c. It is used in the management of Type 2 lepra reaction (ENL)
d. It is teratogenic

Accepted Answer

b, c, d

Answer

a, b, d

Answer

a, b, c

Answer

a, c, d

Question 5

According to the Drugs and Cosmetics Rules, match the following medications with their corresponding schedules: 1. Insulin, 2. Hepatitis B vaccine, 3. Morphine, 4. Veterinary drugs. Schedules: A. Schedule H, B. Schedule Z, C. Schedule G, D. Schedule X.

Accepted Answer

1-C, 2-A, 3-D, 4-B

Answer

1-D, 2-B, 3-A, 4-C

Answer

1-C, 2-D, 3-B, 4-A

Answer

1-B, 2-A, 3-D, 4-C

Question 6

Which of the following statements is incorrect?

Accepted Answer

Cannabis use can result in self-driven, repetitive behaviours

Answer

Alcohol in low dose causes brain stimulation and in higher doses, causes brain suppression

Answer

Opioids are very effective analgesics

Answer

Volatile inhalational agents (when abused) are mostly toxic to humans

Question 7

For benzodiazepines and barbiturates, which of the following is true?

Accepted Answer

Both have effect on GABA-A chloride channel

Answer

Flumazenil is the antidote for barbiturate

Answer

Cause additive sedation with alcohol

Answer

Thiopentone has short duration of action due to metabolism

Question 8

A male patient with a history of MSM presents with urethral discharge. There is penicillin resistance on testing. Which drug should be given?

Accepted Answer

Ceftriaxone

Answer

Amoxiclav

Answer

Tetracycline

Answer

Vancomycin

Question 9

Carbamazepine and erythromycin were given to a patient, and he presented with ataxia and dizziness. Which of the following is the reason for the symptoms?

Accepted Answer

Toxicity of carbamazepine

Answer

Toxicity of erythromycin

Answer

Erythromycin speeds up carbamazepine metabolism

Answer

Sub-therapeutic carbamazepine levels causing seizures

Question 10

Loading dose of an oral drug depends on all of the following except?

Accepted Answer

Half-life

Answer

Volume of distribution

Answer

Plasma concentration

Answer

Bioavailability

INI-CET 2025 — Pharmacology