Mechanism of action of Fenoldopam drug is:
Which of the following anti-epileptics is not given during pregnancy?
Which of the following statements is not true regarding benzodiazepines and barbiturates?
Which of the following is the classical drug for clinical cure in malaria?
Which of the following is not true regarding bempedoic acid?
Which of the following is the treatment for complicated gonorrhoea due to penicillin-resistant Neisseria gonorrhoeae?
In which condition erythropoietin will be useful for treatment?
INI-CET 2025 - Pharmacology INI-CET Practice Questions and MCQs
Question 11: Mechanism of action of Fenoldopam drug is:
- A. Beta-2 agonist
- B. Alpha-1 antagonist
- C. D1 agonist (Correct Answer)
- D. D2 antagonist
Explanation: ***D1 agonist*** - **Fenoldopam** is a selective, short-acting agonist of the **Dopamine-1 (D1) receptor**. - D1 receptor stimulation leads to **vasodilation** in peripheral, coronary, renal, and splanchnic arterial beds, explaining its use as a rapid-acting antihypertensive agent. ***Alpha-1 antagonist*** - Alpha-1 antagonists (e.g., prazosin, doxazosin) block peripheral vasoconstriction and are used for hypertension and BPH, which is not the mechanism of Fenoldopam. - These drugs act by blocking the binding of **norepinephrine** to the alpha-1 receptor on smooth muscle cells. ***Beta-2 agonist*** - Beta-2 agonists (e.g., salbutamol) primarily act as **bronchodilators** by relaxing bronchial smooth muscles, and are unrelated to Fenoldopam's mechanism of action. - They sometimes cause peripheral vasodilation and increased heart rate, but Fenoldopam acts via the D1 receptor. ***D2 antagonist*** - D2 antagonists (e.g., metoclopramide, typical antipsychotics) block dopamine receptors, resulting in antiemetic or antipsychotic effects. - This mechanism is opposite to that of Fenoldopam, which is a dopamine **receptor agonist**.
Question 12: Which of the following anti-epileptics is not given during pregnancy?
- A. Lamotrigine
- B. Carbamazepine
- C. Valproate (Correct Answer)
- D. Levetiracetam
Explanation: ***Correct: Valproate*** - Valproate (Valproic Acid) is the anti-epileptic drug (AED) with the **highest teratogenic risk**, particularly causing **Neural Tube Defects (NTDs)** like spina bifida (1-2% risk), in a dose-dependent manner - It is **strictly contraindicated** during pregnancy (FDA Category X) due to increased risks of **major congenital malformations (10-20%)** and long-term neurodevelopmental consequences, including lower IQ and increased risk of **Autism Spectrum Disorder** in the child - This is the AED that should **NOT be given during pregnancy** *Incorrect: Lamotrigine* - Lamotrigine is generally considered one of the **safer AEDs** used in pregnancy, often a preferred alternative when monotherapy is necessary - While initial data suggested a small risk of oral clefts, current extensive evidence shows it has a **low overall risk** of major congenital malformations - Can be safely used during pregnancy when needed *Incorrect: Levetiracetam* - Levetiracetam (Keppra) is highly favored during pregnancy because it has one of the **lowest risks** of causing major congenital malformations among all AEDs - It is often recommended as the **drug of choice** for women who require AED continuation during gestation due to its favorable safety profile for both physical and neurodevelopmental outcomes *Incorrect: Carbamazepine* - Carbamazepine increases the risk of teratogenicity, classically associated with a risk of **NTDs** (~1%, lower than Valproate) and minor craniofacial defects like cleft lip/palate - Although generally reserved for situations where safer alternatives are ineffective, it **can still be used** when benefits outweigh risks - not absolutely contraindicated like valproate
Question 13: Which of the following statements is not true regarding benzodiazepines and barbiturates?
- A. Both can be used as a sedative hypnotic
- B. With alcohol it causes CNS depression
- C. Both act on GABA-A
- D. Flumazenil can be used for severe alcohol withdrawal symptoms (Correct Answer)
Explanation: ***Flumazenil can be used for severe alcohol withdrawal symptoms*** - This statement is **not true** because **Flumazenil** is a competitive antagonist at the **GABA-A receptor** that specifically reverses the effects of benzodiazepines. - Flumazenil is **contraindicated** in severe alcohol withdrawal, especially when BZDs are used for treatment, as it can precipitate **seizures**. ***Both act on GABA-A*** - This statement is true; both benzodiazepines and barbiturates are **positive allosteric modulators** of the **GABA-A receptor**. - Benzodiazepines increase the **frequency of chloride ion channel opening**, while barbiturates increase the **duration of opening**. ***With alcohol it causes CNS depression*** - This statement is true; both classes exhibit a **synergistic effect** with alcohol, leading to rapid and profound **CNS depression**. - Combining these drugs dramatically increases the risk of respiratory depression, coma, and lethal overdose due to enhanced inhibitory neurotransmission. ***Both can be used as a sedative hypnotic*** - This statement is true; both benzodiazepines (e.g., Diazepam, Clonazepam) and barbiturates (e.g., Phenobarbital) are classified as central nervous system depressants used to produce **sedation** (calmness) or induce **hypnosis** (sleep). - Barbiturates are largely replaced by safer BZDs for hypnotic use due to their lower therapeutic index and higher dependence potential.
Question 14: Which of the following is the classical drug for clinical cure in malaria?
- A. Sulfadoxine-pyrimethamine
- B. Chloroquine (Correct Answer)
- C. Artesunate
- D. Primaquine
Explanation: ***Chloroquine*** - **Clinical cure** in malaria refers to the eradication of the **asexual erythrocytic forms** of the parasite, which are responsible for the clinical symptoms. - **Chloroquine** is the classical 4-aminoquinoline drug historically used as the prototype for clinical cure, acting specifically against asexual blood stages in chloroquine-sensitive *Plasmodium* species. - It remains the drug of choice for *P. vivax*, *P. malariae*, and *P. ovale* in areas without resistance. *Primaquine* - Primarily used for **radical cure** (preventing relapse) by eliminating **hypnozoites** (dormant liver stages) in *P. vivax* and *P. ovale*. - Also kills **gametocytes** (sexual stages) to reduce transmission, but does NOT provide clinical cure as it has minimal activity against asexual blood stages. *Artesunate* - A fast-acting artemisinin derivative that rapidly clears **asexual blood stages** and is used in Artemisinin-based Combination Therapy (ACT) as first-line treatment for *P. falciparum*. - While artesunate does achieve clinical cure in modern practice, chloroquine is the **classical prototype drug** traditionally associated with this concept in pharmacology teaching. *Sulfadoxine-pyrimethamine* - A **folate antagonist** combination used as alternative treatment or for Intermittent Preventive Treatment in Pregnancy (IPTp). - Widespread resistance limits its use for clinical cure, and it's not the classical drug associated with this concept.
Question 15: Which of the following is not true regarding bempedoic acid?
- A. It is a dicarboxylic acid
- B. It is used when statins and diet cannot control dyslipidemia
- C. It non-competitively inhibits ATP citrate lyase (Correct Answer)
- D. It inhibits de-novo synthesis of liver cholesterol
Explanation: ***It non-competitively inhibits ATP citrate lyase*** - This statement is **incorrect** because Bempedoic acid's active metabolite, **ETC-1002-CoA**, inhibits **Adenosine Triphosphate Citrate Lyase (ACL)**, but it does so in a **competitive** manner, not a non-competitive one. - This inhibition leads to reduced acetyl-CoA production in the liver, subsequently lowering **cholesterol synthesis**. ***It is a dicarboxylic acid*** - This statement is **true**. Bempedoic acid (ETC-1002) is structurally a **dicarboxylic acid derivative**, requiring activation in the liver by short-chain acyl-CoA synthetase 1 (ACSVL1). - The presence of the dicarboxylic acid structure is key to its mechanism and selective liver activation. ***It is used when statins and diet cannot control dyslipidemia*** - This statement is **true**. Bempedoic acid is approved primarily for patients with **heterozygous familial hypercholesterolemia** or established **atherosclerotic cardiovascular disease (ASCVD)** who require additional lowering of LDL-C despite maximally tolerated statin therapy. - It is often used as an adjunct to diet and other lipid-lowering therapies, particularly in statin-intolerant patients. ***It inhibits de-novo synthesis of liver cholesterol*** - This statement is **true**. By competitively inhibiting **ATP Citrate Lyase (ACL)**, Bempedoic acid reduces the availability of **acetyl-CoA** in the cytosol, which is the necessary precursor for *de novo* cholesterol synthesis in the liver. - This mechanism is upstream of the HMG-CoA reductase step targeted by statins, offering a complementary path to reducing cholesterol.
Question 16: Which of the following is the treatment for complicated gonorrhoea due to penicillin-resistant Neisseria gonorrhoeae?
- A. Vancomycin
- B. Tetracycline
- C. Ceftriaxone (Correct Answer)
- D. Amoxicillin
Explanation: ***Correct: Ceftriaxone*** - **Ceftriaxone** (a third-generation cephalosporin) is the current cornerstone of treatment for both uncomplicated and complicated gonorrhoea, especially given the high prevalence of **penicillin resistance** in *N. gonorrhoeae*. - For complicated infections (e.g., disseminated gonococcal infection, epididymo-orchitis, pelvic inflammatory disease), it is often given as a higher dose (e.g., 1g IV daily) and sometimes combined with **azithromycin** where co-infection with *Chlamydia* is possible. *Incorrect: Amoxicillin* - **Amoxicillin** is a penicillin-class antibiotic and is ineffective due to widespread resistance mediated by **plasmid-encoded beta-lactamases** (e.g., *penicillinase-producing Neisseria gonorrhoeae* or PPNG). - Penicillins are no longer recommended for the treatment of gonorrhoea in any setting because of this high resistance. *Incorrect: Tetracycline* - **Tetracycline** (or doxycycline) was historically used for gonorrhoea treatment but resistance has become common, rendering it unreliable as a first-line therapy. - It is currently used primarily to treat concurrent **Chlamydia trachomatis** infection, rather than gonorrhoea itself. *Incorrect: Vancomycin* - **Vancomycin** is a glycopeptide antibiotic primarily effective against **Gram-positive bacteria** (like MRSA) by interfering with cell wall synthesis. - *Neisseria gonorrhoeae* is a **Gram-negative bacterium**, and vancomycin is not effective for its treatment.
Question 17: In which condition erythropoietin will be useful for treatment?
- A. Nutritional anemia
- B. Aplastic anemia
- C. Anemia in chronic kidney disease (Correct Answer)
- D. Anemia in myelodysplastic syndrome
Explanation: ***Anemia in chronic kidney disease*** - **Erythropoietin (EPO)** deficiency is the primary cause of anemia in chronic kidney disease (**CKD**), as the damaged kidneys cannot produce adequate amounts. - Recombinant human EPO (**rHuEPO**) is the standard treatment to stimulate **erythropoiesis** in the bone marrow, correcting the anemia and improving quality of life. ***Anemia in myelodysplastic syndrome*** - While erythropoiesis-stimulating agents (ESAs) like EPO are occasionally used in lower-risk myelodysplastic syndrome (**MDS**) patients, especially those who are transfusion-dependent, the response rates are variable and dependent on underlying cytogenetics and serum EPO levels. - The primary defect in MDS involves abnormal **hematopoietic stem cell function** (a primary bone marrow failure) rather than just EPO deficiency, making treatment difficult. ***Nutritional anemia*** - This category, including **iron deficiency anemia** and **megaloblastic anemia** (Vitamin B12 or folate deficiency), is primarily treated by supplementing the specific deficient nutrient. - Giving EPO would be ineffective unless the underlying nutritional deficit is corrected, as the bone marrow lacks the necessary building blocks for red blood cell production. ***Aplastic anemia*** - Aplastic anemia is a condition of **pancytopenia** caused by bone marrow failure due to the destruction or suppression of hematopoietic stem cells, often immune-mediated. - The primary treatment involves **immunosuppressive therapy** (e.g., antithymocyte globulin) or **hematopoietic stem cell transplantation**, as erythropoietin production is usually adequate, and the bone marrow is simply unable to respond.