NEET-PG 2013 - Pharmacology Practice Questions

Q: Drug of choice for open angle glaucoma:

Latanoprost. ***Latanoprost*** - **Prostaglandin F2α analogs** like latanoprost are generally considered **first-line therapy** for open-angle glaucoma due to their efficacy and once-daily dosing. - They work by **increasing uveoscleral outflow** of aqueous humor, thereby lowering intraocular pressure (IOP). *Acetazolamide* - **Acetazolamide** is a **carbonic anhydrase inhibitor** that reduces aqueous humor production. - It is typically used for **acute angle-closure glaucoma** or when initial treatments fail, often due to systemic side effects with long-term use. *Timolol* - **Timolol** is a **non-selective beta-blocker** that reduces aqueous humor production. - While effective, it is often a second-line agent or used in combination due to potential systemic side effects like **bronchospasm** and **bradycardia**. *Brimonidine* - **Brimonidine** is an **alpha-2 adrenergic agonist** that reduces aqueous humor production and increases uveoscleral outflow. - It is typically used as a second-line agent or in combination therapy due to potential side effects like **ocular pruritus** and **allergic conjunctivitis**.

Q: Which of the following antiglaucoma medications can cause drowsiness?

Brimonidine. ***Brimonidine*** - **Brimonidine** is an **alpha-2 adrenergic agonist** [1] that can cause central nervous system depression, leading to side effects such as **drowsiness** and fatigue. - This systemic side effect is more common with the topical ophthalmic formulation due to systemic absorption. *Latanoprost* - **Latanoprost** is a **prostaglandin analog** that primarily works by increasing uveoscleral outflow, and its side effects are mainly localized to the eye (e.g., iris color change, eyelash growth). - It does not typically cause systemic side effects like drowsiness because its systemic absorption is minimal. *Dorzolamide* - **Dorzolamide** is a **topical carbonic anhydrase inhibitor** [1] that reduces aqueous humor production, and its most common side effects include local ocular irritation and a bitter taste. - While systemic carbonic anhydrase inhibitors can cause fatigue and drowsiness, the topical formulation has very limited systemic absorption, making drowsiness uncommon. *Timolol* - **Timolol** is a **non-selective beta-blocker** [1] that reduces aqueous humor production and can cause systemic side effects such as bradycardia, bronchospasm, and hypotension. - While some beta-blockers can cause fatigue, **drowsiness** as a prominent side effect is less common compared to alpha-2 agonists.

Q: What is the drug of choice for managing generalized tonic-clonic seizures (GTCS) during pregnancy?

Lamotrigine. ***Lamotrigine*** - **Lamotrigine** is considered **one of the preferred drugs** for managing epilepsy during pregnancy due to its relatively **low teratogenic risk** compared to older antiepileptic drugs. - Its established safety profile in pregnancy makes it a preferred option to balance seizure control and **fetal well-being**. - **Important Note:** For **GTCS specifically**, lamotrigine and levetiracetam are both considered appropriate first-line choices, with selection depending on individual patient factors and seizure control history. - Lamotrigine levels **decrease during pregnancy** and require monitoring and dose adjustments. *CBZ* - **Carbamazepine (CBZ)** is associated with an increased risk of **neural tube defects** and other congenital malformations when used during pregnancy, making it less favorable. - While effective for GTCS, its teratogenicity often leads to avoidance or careful consideration of alternatives in pregnant women. *Levetiracetam* - **Levetiracetam** is increasingly recognized as an **excellent choice for GTCS in pregnancy** with a favorable safety profile and growing evidence base. - Many recent guidelines and clinical practices favor levetiracetam as **first-line for GTCS** due to its low risk of major congenital malformations and good efficacy. - It is a **medically appropriate alternative** to lamotrigine, and in some contexts may be preferred, particularly for primary generalized epilepsy. *Valproate* - **Valproate** has the highest risk of **teratogenicity** among common antiepileptic drugs, including a significant risk of **neural tube defects**, developmental delay, autism spectrum disorder, and other anomalies. - Due to these significant risks, valproate is generally **contraindicated** in women of childbearing potential, especially during pregnancy, unless no other effective and safer alternative exists.

Q: What is the drug of choice for most forms of interstitial lung disease?

Corticosteroids. ***Corticosteroids*** - **Corticosteroids** are the **drug of choice** for many forms of **interstitial lung disease (ILD)** due to their potent **anti-inflammatory** and **immunosuppressive properties**, which help reduce lung inflammation and prevent fibrosis. - They are particularly effective in inflammatory ILDs such as **sarcoidosis**, **hypersensitivity pneumonitis**, and some **connective tissue disease-associated ILDs**. *Antibiotics* - **Antibiotics** are primarily used to treat bacterial and other microbial infections and are **not effective** against the **inflammatory and fibrotic processes** characteristic of most ILDs. - They might be used if there's a **secondary bacterial infection** complicating ILD, but not as primary treatment for the ILD itself. *Bronchodilators* - **Bronchodilators** work by relaxing the muscles around the airways, making them wider and easier to breathe through, which is beneficial in conditions like **asthma** or **COPD**. - They are **not primarily used** in ILD as the main problem is **inflammation and scarring of the lung tissue**, not reversible airway constriction. *Aspirin* - **Aspirin** is an **NSAID** with **anti-inflammatory**, **anti-platelet**, and **analgesic properties**, commonly used for pain relief, fever reduction, and cardiovascular protection. - It has **no established role** in the primary treatment of **interstitial lung disease**, as its anti-inflammatory effects are typically insufficient for the severe inflammation seen in ILD.

Q: All are symptoms of morphine withdrawal except?

Fall in BP. ***Fall in BP*** - **Hypotension (fall in BP)** is **not** typically a symptom of opioid withdrawal; rather, **hypertension** can occur due to sympathetic overdrive. - Opioid withdrawal symptoms are primarily characterized by **hyperactivity** and increased sympathetic nervous system activity. *Mydriasis* - **Mydriasis (dilated pupils)** is a classic symptom of opioid withdrawal, resulting from reduced parasympathetic tone and increased sympathetic activity. - In contrast, opioid intoxication causes **miosis (pinpoint pupils)**. *Yawning* - **Yawning** is a very common and early symptom of opioid withdrawal, often accompanied by feelings of fatigue and restlessness. - It reflects generalized **autonomic dysregulation** during withdrawal. *Lacrimation* - **Lacrimation (tearing)** is another prominent autonomic symptom of opioid withdrawal. - This, along with rhinorrhea, contributes to the **"flu-like" symptoms** experienced during withdrawal.

Q: Which of the following medications is not typically used for the treatment of erectile dysfunction?

Beta blockers. ***Beta blockers*** - **Beta blockers** are primarily used to treat conditions like **hypertension** and **heart disease**. - While they can cause ED as a side effect, they are **not used for its treatment**. *Sildenafil* - **Sildenafil** is a **PDE5 inhibitor** that works by increasing **blood flow to the penis**, facilitating an erection. - It is a **first-line oral medication** widely prescribed for erectile dysfunction. *PG-E* - **PG-E** refers to **Prostaglandin E1** (alprostadil), which can be administered via **intracavernosal injection** or **urethral suppository**. - It directly causes **vasodilation** in the penis, leading to an erection, and is used when oral medications are ineffective or contraindicated. *Papaverine* - **Papaverine** is a **non-specific vasodilator** that can be used as an **intracavernosal injection** for ED. - It works by relaxing **smooth muscle** in the penile arteries, increasing blood flow and inducing an erection, often used in combination with phentolamine.

Q: The mechanism by which ergometrine stops postpartum hemorrhage is that it:

Increases tone of uterine muscle. ***Increases tone of uterine muscle*** - **Ergometrine** is an **ergot alkaloid** that directly stimulates **uterine smooth muscle contractions**. - These sustained contractions lead to **compression of blood vessels within the myometrium**, thereby reducing blood flow and controlling **postpartum hemorrhage**. *Causes vasoconstriction of uterine arteries* - While ergometrine does have some generalized **vasoconstrictive effects**, its primary mechanism of action in controlling postpartum hemorrhage is not mainly through direct vasoconstriction of large uterine arteries. - The crucial effect is the **sustained uterine contraction** which mechanically occludes blood vessels, rather than chemical constriction of the vessels themselves. *Induces platelet aggregation* - Ergometrine does not primarily act by inducing **platelet aggregation**; this is a function of specific clotting factors and platelet activators. - Its therapeutic effect against hemorrhage is mediated through its action on **uterine contractility**, not on the cellular components of coagulation. *Promotes coagulation* - Ergometrine does not directly promote the **coagulation cascade** or enhance the formation of fibrin clots. - Its mechanism of action is distinct from agents that affect intrinsic or extrinsic pathways of coagulation.

Q: Which local anaesthetic is known to cause methemoglobinemia?

Prilocaine. ***Prilocaine*** - **Prilocaine** is metabolized into **ortho-toluidine**, which can oxidize hemoglobin to **methemoglobin**, especially at higher doses or in susceptible individuals. - **Methemoglobinemia** symptoms include **cyanosis**, **dyspnea**, and in severe cases, central nervous system depression, due to reduced oxygen-carrying capacity of blood. *Procaine* - **Procaine** is an ester-type local anesthetic. It is metabolized to **para-aminobenzoic acid (PABA)**, which can cause allergic reactions, but it is not associated with methemoglobinemia. - It has a relatively **short duration of action** and is less commonly used now compared to amide-type local anesthetics. *Etidocaine* - **Etidocaine** is an amide-type local anesthetic that is known for its **long duration of action** and high potency. - While it can cause systemic toxicity with high doses due to its cardiac and neurological effects, **methemoglobinemia** is not a characteristic side effect. *Ropivacaine* - **Ropivacaine** is an amide-type local anesthetic similar to bupivacaine, known for its **motor-sparing effect** and use in regional anesthesia. - It is associated with a lower risk of **cardiotoxicity** compared to bupivacaine but does not cause methemoglobinemia.

Q: In pseudocholinesterase deficiency, which drug should be used cautiously?

Succinylcholine. ***Succinylcholine*** - **Succinylcholine** is primarily metabolized by **pseudocholinesterase** (also known as butyrylcholinesterase). - In individuals with **pseudocholinesterase deficiency**, the metabolism of succinylcholine is significantly delayed, leading to **prolonged neuromuscular blockade** and extended paralysis. *Barbiturates* - **Barbiturates** are mainly metabolized by the **hepatic cytochrome P450 system** and do not depend on pseudocholinesterase for their breakdown. - Their metabolism would not be significantly affected by pseudocholinesterase deficiency. *Halothane (an inhalational anesthetic)* - **Halothane** is primarily metabolized by the **hepatic cytochrome P450 system** and excreted via the lungs. - Its metabolism is unrelated to **pseudocholinesterase activity**. *Gallamine (a neuromuscular blocker)* - **Gallamine** is a **nondepolarizing neuromuscular blocker** that is primarily eliminated by **renal excretion** as an unchanged drug. - Its metabolism and elimination are independent of **pseudocholinesterase**.

Q: In ophthalmology, if a patient is allergic to aminoesters, which local anesthetic can be safely used?

Prilocaine. **Local anesthetics are classified into two chemical groups: esters (aminoesters) and amides. Allergies to esters typically do not cross-react with amides.** ***Prilocaine*** - **Prilocaine** is an **amide-type local anesthetic**, and allergies to **aminoesters** typically do not cross-react with **amides**. - It is a safe alternative in patients with a known allergy to **ester-type local anesthetics**. *Cocaine* - **Cocaine** is an **ester-type local anesthetic**, sharing a similar chemical structure with **aminoesters**. - Patients allergic to **aminoesters** are likely to experience a **cross-reaction** with **cocaine**. *Procaine* - **Procaine** is a classic **ester-type local anesthetic** (an aminoester). - An allergy to aminoesters directly implies an allergy to **procaine** due to its chemical classification. *Tetracaine* - **Tetracaine** is also an **ester-type local anesthetic** (an aminoester). - It is contraindicated in patients with an allergy to **aminoesters** due to the high risk of **allergic reaction**.

Question 1

Drug of choice for open angle glaucoma:

Accepted Answer

Latanoprost

Answer

Acetazolamide

Answer

Brimonidine

Answer

Timolol

Question 2

Which of the following antiglaucoma medications can cause drowsiness?

Accepted Answer

Brimonidine

Answer

Latanoprost

Answer

Dorzolamide

Answer

Timolol

Question 3

What is the drug of choice for managing generalized tonic-clonic seizures (GTCS) during pregnancy?

Accepted Answer

Lamotrigine

Answer

CBZ

Answer

Levetiracetam

Answer

Valproate

Question 4

What is the drug of choice for most forms of interstitial lung disease?

Accepted Answer

Corticosteroids

Answer

Antibiotics

Answer

Bronchodilators

Answer

Aspirin

Question 5

All are symptoms of morphine withdrawal except?

Accepted Answer

Fall in BP

Answer

Yawning

Answer

Lacrimation

Answer

Mydriasis

Question 6

Which of the following medications is not typically used for the treatment of erectile dysfunction?

Accepted Answer

Beta blockers

Answer

Papaverine

Answer

Sildenafil

Answer

PG-E

Question 7

The mechanism by which ergometrine stops postpartum hemorrhage is that it:

Accepted Answer

Increases tone of uterine muscle

Answer

Induces platelet aggregation

Answer

Promotes coagulation

Answer

Causes vasoconstriction of uterine arteries

Question 8

Which local anaesthetic is known to cause methemoglobinemia?

Accepted Answer

Prilocaine

Answer

Procaine

Answer

Ropivacaine

Answer

Etidocaine

Question 9

In pseudocholinesterase deficiency, which drug should be used cautiously?

Accepted Answer

Succinylcholine

Answer

Barbiturates

Answer

Gallamine

Answer

Halothane

Question 10

In ophthalmology, if a patient is allergic to aminoesters, which local anesthetic can be safely used?

Accepted Answer

Prilocaine

Answer

Procaine

Answer

Cocaine

Answer

Tetracaine

NEET-PG 2013 — Pharmacology