NEET-PG 2024 Practice Questions

Q: A woman at 8 weeks of gestation is diagnosed with hyperthyroidism. Which of the following is the most appropriate treatment option?

Propylthiouracil. ***Propylthiouracil*** - **Propylthiouracil (PTU)** is the preferred treatment for hyperthyroidism in the **first trimester** of pregnancy due to a lower risk of teratogenic effects compared to methimazole. - While PTU carries a risk of **liver toxicity**, its use is generally favored in early pregnancy to avoid the more severe potential fetal abnormalities associated with other antithyroid drugs during this critical developmental period. *Methimazole* - **Methimazole** is associated with a specific pattern of birth defects, including **aplasia cutis congenita** (scalp defects) and **esophageal/choanal atresia**, when used during the first trimester. - It is generally preferred in the **second and third trimesters** due to a lower risk of maternal hepatotoxicity compared to PTU. *Carbimazole* - **Carbimazole** is a **prodrug** that is metabolized to methimazole; therefore, it carries the same teratogenic risks as methimazole in the first trimester. - Its use during early pregnancy is generally avoided for the same reasons as methimazole. *Radioactive iodine* - **Radioactive iodine (RAI)** is **contraindicated** in pregnancy because it crosses the placenta and can cause **fetal hypothyroidism** and irreversible destruction of the fetal thyroid gland. - It is an effective treatment for hyperthyroidism outside of pregnancy but is never used during gestation.

Q: A woman at 30 weeks of gestation is diagnosed with deep vein thrombosis (DVT). Which of the following is the most appropriate treatment for this patient?

Low Molecular Weight Heparin (LMWH). ***Low Molecular Weight Heparin (LMWH)*** - **LMWH** is the preferred anticoagulant for DVT during pregnancy because it does **not cross the placenta**, making it safe for the fetus. - It also has a **predictable anticoagulant response** and a lower risk of **heparin-induced thrombocytopenia (HIT)** compared to unfractionated heparin. *Warfarin* - **Warfarin is teratogenic**, especially during the first trimester, and can cause **fetal warfarin syndrome**, which includes skeletal and central nervous system abnormalities. - It can also lead to **fetal bleeding** and miscarriage at any stage of pregnancy. *Apixaban* - **Apixaban** is a **direct oral anticoagulant (DOAC)**, and its safety in pregnancy has not been established. - There is insufficient data regarding its **placental transfer** and potential fetal effects, making its use generally contraindicated in pregnant women. *Fondaparinux* - While **fondaparinux** is an indirect Factor Xa inhibitor and might be considered in cases of heparin allergy or intolerance, its **safety profile in pregnancy is not as well-established** as LMWH. - It is generally reserved for situations where LMWH cannot be used, and its use requires careful consideration due to limited data.

Q: Aprepitant is a drug used in the treatment of some cases of chemotherapy-induced nausea and vomiting. What is the mechanism of action of this drug?

NK1 antagonist. ***NK1 antagonist*** - **Aprepitant** is a selective, high-affinity antagonist of the **neurokinin 1 (NK1) receptor**, which is activated by **substance P**. - By blocking NK1 receptors in the brainstem's **vomiting center**, aprepitant prevents nausea and vomiting, especially in chemotherapy-induced cases. - Aprepitant is particularly effective for **acute and delayed** chemotherapy-induced nausea and vomiting (CINV). *NK3 antagonist* - While **neurokinin 3 (NK3) receptors** are present in the central nervous system, their specific role in chemotherapy-induced nausea and vomiting is less prominent. - Aprepitant does not primarily target NK3 receptors; its antiemetic action is mediated through NK1 blockade. *NK1 agonist* - An **NK1 agonist** would activate the NK1 receptor, potentially *inducing* nausea and vomiting, which is the opposite of the desired therapeutic effect of aprepitant. - Agonists are typically used to stimulate a receptor, not block it as is done with aprepitant. *NK2 antagonist* - **Neurokinin 2 (NK2) receptors** are also part of the tachykinin receptor family, but they are not the primary target for antiemetic drugs like aprepitant. - While NK2 receptors play roles in smooth muscle contraction and inflammation, blocking them is not the mechanism by which aprepitant prevents nausea and vomiting. - Aprepitant's antiemetic efficacy is specifically due to **NK1 receptor antagonism**. *NK2 agonist* - **Neurokinin 2 (NK2) receptors** are also part of the tachykinin receptor family, but they are not the primary target for antiemetic drugs like aprepitant. - Activating NK2 receptors would not provide the antiemetic effect seen with aprepitant, as NK1 receptor antagonism is crucial.

Q: Which of the following is represented in the below figure by drug X?

Epsilon Amino Caproic acid. ***Epsilon Amino Caproic acid*** - The diagram shows **Drug X** inhibiting the activation of plasminogen to plasmin, thereby reducing fibrinolysis. - **Epsilon aminocaproic acid (EACA)** is an antifibrinolytic drug that competitively inhibits plasminogen activators, thus preventing the formation of plasmin. *Clopidogrel* - **Clopidogrel** is an **antiplatelet drug** that works by inhibiting the P2Y12 ADP receptor on platelets, preventing platelet aggregation. - Its mechanism of action is distinct from the fibrinolytic pathway shown in the diagram. *Tenecteplase* - **Tenecteplase** is a **thrombolytic drug** (fibrinolytic) that *activates* plasminogen to plasmin. - This action is opposite to what Drug X depicts, which *inhibits* the fibrinolytic pathway. *Streptokinase* - **Streptokinase** is a **thrombolytic drug** that activates plasminogen to plasmin, promoting fibrinolysis. - Like tenecteplase, its action is opposite to Drug X, which inhibits the fibrinolytic pathway. *Aspirin* - **Aspirin** is an **antiplatelet drug** that inhibits cyclooxygenase-1 (COX-1), thereby reducing thromboxane A2 production and platelet aggregation. - It does not directly interact with the plasminogen-plasmin system as depicted for Drug X.

Q: A patient presents with hypertension and has a history of renal stones, along with several episodes of renal colic. Which diuretic is the most appropriate to use?

Hydrochlorothiazide. **Hydrochlorothiazide** - **Thiazide diuretics** like hydrochlorothiazide reduce urinary calcium excretion, which is beneficial in patients with a history of **calcium renal stones**. - This effect helps prevent the recurrence of renal stones while also treating hypertension. - Among thiazide and thiazide-like diuretics, hydrochlorothiazide has the **most established evidence** for preventing calcium stone recurrence. *Furosemide* - Furosemide is a **loop diuretic** that increases urinary calcium excretion, which would exacerbate the risk of renal stone formation. - While effective for hypertension, its effect on calcium makes it unsuitable for this patient. *Ethacrynic acid* - Ethacrynic acid is also a **loop diuretic** with similar effects to furosemide, including increasing urinary calcium excretion. - This makes it an inappropriate choice for a patient with a history of renal stones. *Spironolactone* - Spironolactone is a **potassium-sparing diuretic** that works by antagonizing aldosterone, primarily affecting sodium and potassium excretion. - It does not significantly impact urinary calcium excretion in a way that would prevent calcium renal stones, nor is it a first-line agent for hypertension with co-existing renal stones. *Indapamide* - Indapamide is a **thiazide-like diuretic** with some calcium-retaining properties, but it is less effective than hydrochlorothiazide in reducing calcium excretion. - While it can be used for hypertension, **hydrochlorothiazide is preferred** specifically for preventing calcium stone recurrence due to stronger evidence and greater effect on reducing urinary calcium.

Q: Which of the following is the most appropriate treatment for an overactive bladder in a patient with dementia?

Tolterodine. ***Tolterodine*** - **Tolterodine** is a **muscarinic antagonist** that blocks acetylcholine receptors in the bladder, reducing detrusor muscle contractions and overactive bladder symptoms. - Unlike some other anticholinergics like oxybutynin, it has a **lower propensity to cross the blood-brain barrier** and thus a reduced risk of exacerbating cognitive impairment in patients with dementia. *Mirabegron* - **Mirabegron** is a **beta-3 adrenergic agonist** that relaxes the detrusor muscle, increasing bladder capacity. - While it has a different mechanism of action and is less likely to cause anticholinergic cognitive side effects than older anticholinergics, it can still cause **hypertension** and **tachycardia**, which may be problematic in elderly patients with comorbidities. *Behavioral therapy/bladder training* - **Behavioral therapy** and **bladder training** are important first-line treatments for overactive bladder. - However, for patients with **dementia**, cognitive impairment often makes adherence to and understanding of these complex therapies challenging or impossible without significant caregiver support. *Oxybutynin* - **Oxybutynin** is an **anticholinergic drug** that is effective for overactive bladder. - However, it has a **high affinity for muscarinic receptors** in the brain and readily crosses the blood-brain barrier, significantly increasing the risk of **cognitive impairment, confusion, and delirium** in elderly patients, especially those with pre-existing dementia. *Trospium* - **Trospium** is a **quaternary amine anticholinergic** that is hydrophilic and has minimal blood-brain barrier penetration. - While theoretically safer than oxybutynin in terms of CNS effects, it has **lower bladder selectivity** compared to tolterodine and may cause more peripheral anticholinergic side effects (dry mouth, constipation).

Q: Which of the following statements regarding the patch shown in the figure is correct?

Excessive use can result in methemoglobinemia.. ***Excessive use can result in methemoglobinemia.*** - The patch shown is likely an **EMLA patch**, which contains **lidocaine** and **prilocaine**. Excessive absorption of prilocaine, especially with large doses or prolonged application, can lead to the formation of **methemoglobinemia**. - **Prilocaine** is metabolized into **ortho-toluidine**, which is an oxidizing agent that can convert hemoglobin to methemoglobin, reducing the blood's oxygen-carrying capacity. *It is an equal mixture of local anesthetics.* - The EMLA patch is a 1:1 mixture of **lidocaine** and **prilocaine**, but the claim that it contains "an equal mixture of local anesthetics" is vague and could imply other compositions not specific to EMLA. - While it's an equal ratio of two specific local anesthetics, the option's wording is not precise enough to be the *most correct* statement. *5 ml of a 5 percent mixture contains 50 mg of lignocaine.* - A 5% solution means 5 grams (5000 mg) per 100 ml. Therefore, 1 ml contains 50 mg of lignocaine. - Thus, 5 ml of a 5% mixture would contain 250 mg of **lignocaine**, not 50 mg. This statement is mathematically incorrect. *It contains lignocaine and ropivacaine in a ratio of 50 percent each.* - **EMLA patches** contain **lidocaine** (lignocaine) and **prilocaine**, not ropivacaine. - While it is a 50% concentration for each active ingredient, the specific combination of local anesthetics mentioned in this option is incorrect. *It should be applied for at least 2 hours before minor procedures.* - For most minor procedures, **EMLA cream** typically requires **30-60 minutes** of application time to achieve adequate topical anesthesia. - While longer application times (up to 2 hours) may enhance depth of anesthesia for certain procedures, stating that it "should be applied for at least 2 hours" is excessive and not a standard recommendation for minor procedures.

Q: Lidocaine is used in a loading dose for the treatment of arrhythmias. The loading dose of this drug depends upon which of the following factors?

Volume of distribution. ***Volume of distribution*** - The **loading dose** of a drug is primarily determined by its **volume of distribution (Vd)** and the **target plasma concentration**. - A larger **Vd** means the drug distributes widely into tissues, requiring a larger loading dose to achieve the desired concentration in the central compartment. *Clearance* - **Clearance** dictates the **maintenance dose** needed to sustain a steady-state concentration once the loading dose has been administered. - It reflects the rate at which the drug is eliminated from the body, not how much is initially needed to fill the distribution volume. *Half-life* - **Half-life** determines the **time required to reach steady-state** and the **dosing interval** for maintaining therapeutic concentrations. - While related to clearance and Vd, it does not directly determine the magnitude of the initial loading dose itself. *Bioavailability* - **Bioavailability** is the fraction of administered drug that reaches the systemic circulation in an unchanged form. - It influences the oral dose required to achieve a certain plasma concentration, but the concept of loading dose is typically considered for the intravenous route where bioavailability is 100%. *Elimination rate constant* - The **elimination rate constant (ke)** describes the rate of drug elimination and is related to clearance and volume of distribution (ke = Cl/Vd). - Like clearance, it determines the **maintenance dose** and dosing frequency, not the initial loading dose required to achieve therapeutic levels.

Q: A person was taking an antihypertensive drug and continued taking it despite developing constipation, dry mouth, and dizziness. He was taking it regularly but forgot to take it during a trip abroad and has now developed a hypertensive emergency. Which antihypertensive was he likely taking?

Clonidine. **Clonidine** - The described symptoms of **constipation, dry mouth, and dizziness** are common side effects of **clonidine**, an alpha-2 adrenergic agonist. - The development of a **hypertensive emergency** upon abrupt cessation of the drug strongly suggests clonidine, as it is known for causing **rebound hypertension** due to a sudden increase in sympathetic outflow. *Amlodipine* - **Amlodipine**, a dihydropyridine calcium channel blocker, primarily causes **peripheral edema, headache, and flushing**, not typically constipation or rebound hypertension upon withdrawal. - While it can cause dizziness, the combination of side effects and withdrawal symptoms does not fit amlodipine. *Lisinopril* - **Lisinopril**, an ACE inhibitor, is known for causing **cough and angioedema**. - It does not typically cause constipation, dry mouth, or rebound hypertension upon discontinuation. *Telmisartan* - **Telmisartan**, an angiotensin receptor blocker (ARB), generally has a **favorable side effect profile** and does not commonly cause constipation or dry mouth. - Withdrawal of ARBs does not typically lead to a **hypertensive emergency** in the way clonidine does. *Metoprolol* - **Metoprolol**, a beta-blocker, can cause **fatigue and bradycardia** but does not typically cause the anticholinergic effects (dry mouth, constipation) seen with clonidine. - While abrupt withdrawal of beta-blockers can lead to rebound tachycardia and hypertension, the severity and acute nature of the hypertensive emergency described is more characteristic of clonidine withdrawal.

Question 1

A woman at 8 weeks of gestation is diagnosed with hyperthyroidism. Which of the following is the most appropriate treatment option?

Accepted Answer

Propylthiouracil

Answer

Methimazole

Answer

Carbimazole

Answer

Radioactive iodine

Question 2

A woman at 30 weeks of gestation is diagnosed with deep vein thrombosis (DVT). Which of the following is the most appropriate treatment for this patient?

Accepted Answer

Low Molecular Weight Heparin (LMWH)

Answer

Warfarin

Answer

Apixaban

Answer

Fondaparinux

Question 3

Aprepitant is a drug used in the treatment of some cases of chemotherapy-induced nausea and vomiting. What is the mechanism of action of this drug?

Accepted Answer

NK1 antagonist

Answer

NK3 antagonist

Answer

NK1 agonist

Answer

NK2 agonist

Answer

NK2 antagonist

Question 4

Which of the following is an inclusion criterion for the shorter bedaquiline regimen in the treatment of tuberculosis?

Accepted Answer

Rifampicin-resistant but fluoroquinolone-sensitive TB

Answer

Extrapulmonary TB like Tubercular meningitis

Answer

Rifampicin resistance with both KatG and inhA mutation

Answer

Rifampicin-sensitive TB

Answer

Extensively drug-resistant TB (XDR-TB)

Question 5

Which of the following is represented in the below figure by drug X?

Accepted Answer

Epsilon Amino Caproic acid

Answer

Clopidogrel

Answer

Tenecteplase

Answer

Aspirin

Answer

Streptokinase

Question 6

A patient presents with hypertension and has a history of renal stones, along with several episodes of renal colic. Which diuretic is the most appropriate to use?

Accepted Answer

Hydrochlorothiazide

Answer

Furosemide

Answer

Ethacrynic acid

Answer

Spironolactone

Answer

Indapamide

Question 7

Which of the following is the most appropriate treatment for an overactive bladder in a patient with dementia?

Accepted Answer

Tolterodine

Answer

Mirabegron

Answer

Behavioral therapy/bladder training

Answer

Oxybutynin

Answer

Trospium

Question 8

Which of the following statements regarding the patch shown in the figure is correct?

Accepted Answer

Excessive use can result in methemoglobinemia.

Answer

It is an equal mixture of local anesthetics.

Answer

5 ml of a 5 percent mixture contains 50 mg of lignocaine.

Answer

It contains lignocaine and ropivacaine in a ratio of 50 percent each.

Answer

It should be applied for at least 2 hours before minor procedures.

Question 9

Lidocaine is used in a loading dose for the treatment of arrhythmias. The loading dose of this drug depends upon which of the following factors?

Accepted Answer

Volume of distribution

Answer

Clearance

Answer

Half-life

Answer

Bioavailability

Answer

Elimination rate constant

Question 10

A person was taking an antihypertensive drug and continued taking it despite developing constipation, dry mouth, and dizziness. He was taking it regularly but forgot to take it during a trip abroad and has now developed a hypertensive emergency. Which antihypertensive was he likely taking?

Accepted Answer

Clonidine

Answer

Amlodipine

Answer

Lisinopril

Answer

Telmisartan

Answer

Metoprolol

NEET-PG 2024

OB/GYN

Obstetrics and Gynecology

Pharmacology