What is the recommended regimen for post-exposure prophylaxis for HIV?
In areas with chloroquine-sensitive P. vivax, what is the preferred drug for treating the blood stages?
What is the recommended therapeutic supplementation of iron and folic acid for adults with deficiency?
Best method of treatment for methyl alcohol poisoning is:
When alcohol is consumed with aerated soft drinks -
From which part of the Papaver somniferum plant does the latex, commonly referred to as 'milk', exude?
Which of the following substances is commonly known as an arrow poison used by indigenous South American tribes?
In the context of pharmacology, what is the term 'Mickey Finn' commonly associated with?
Digitalis is used in mitral stenosis to control the ventricular rate when the patient develops which condition?
All of the following are characteristic features of treatment of iron deficiency anemia with oral iron supplements, except which of the following?
NEET-PG 2015 - Pharmacology NEET-PG Practice Questions and MCQs
Question 101: What is the recommended regimen for post-exposure prophylaxis for HIV?
- A. Zidovudine + Lamivudine + Lopinavir/ritonavir for 28 days
- B. Tenofovir disoproxil fumarate + Emtricitabine + Raltegravir for 28 days
- C. Single dose Tenofovir + Emtricitabine + Raltegravir
- D. Tenofovir disoproxil fumarate + Emtricitabine + Dolutegravir for 28 days (Correct Answer)
Explanation: ***Tenofovir disoproxil fumarate + Emtricitabine + Dolutegravir for 28 days*** - This is the **current first-line recommended regimen** for **HIV post-exposure prophylaxis (PEP)** according to WHO (2021), CDC, and Indian NACO guidelines. - It includes two **nucleoside reverse transcriptase inhibitors (NRTIs)** and an **integrase strand transfer inhibitor (INSTI)**. - **Dolutegravir** is preferred over Raltegravir due to **superior efficacy, better tolerability, higher barrier to resistance, once-daily dosing**, and fewer drug interactions. - The duration of **28 days** is crucial for effective PEP to cover the window period for potential HIV integration and replication. *Tenofovir disoproxil fumarate + Emtricitabine + Raltegravir for 28 days* - This was the **previous standard PEP regimen** and is still an acceptable alternative if Dolutegravir is contraindicated or unavailable. - Raltegravir requires **twice-daily dosing** compared to Dolutegravir's once-daily regimen, which may affect adherence. - The 28-day duration is correct, but Raltegravir is no longer the first-line INSTI choice in current guidelines. *Single dose Tenofovir + Emtricitabine + Raltegravir* - A **single dose** of these medications is insufficient for **post-exposure prophylaxis (PEP)** as HIV replication needs to be suppressed over an extended period to prevent seroconversion. - PEP typically requires a **28-day course** to be effective. *Zidovudine + Lamivudine + Lopinavir/ritonavir for 28 days* - While this is an older, effective **antiretroviral regimen**, it is **not the preferred first-line PEP regimen** due to a higher incidence of side effects, particularly with zidovudine (anemia, nausea). - Modern guidelines favor regimens with **Tenofovir/Emtricitabine + Dolutegravir** due to better tolerability and superior efficacy.
Question 102: In areas with chloroquine-sensitive P. vivax, what is the preferred drug for treating the blood stages?
- A. Mefloquine
- B. Artesunate
- C. Quinine
- D. Chloroquine (Correct Answer)
Explanation: ***Correct Option: Chloroquine***- **Chloroquine** remains the **first-line treatment** for **chloroquine-sensitive P. vivax** infections due to its high efficacy and safety profile [1, 2].- It rapidly clears **blood-stage parasites**, alleviating acute symptoms of malaria [3].- In areas where P. vivax remains sensitive, chloroquine is preferred due to low cost, good tolerability, and proven effectiveness [1, 2].*Incorrect Option: Mefloquine*- **Mefloquine** is typically reserved for areas with **chloroquine-resistant P. falciparum** or for prophylaxis in such regions.- Its use is generally avoided when less toxic and equally effective options like chloroquine are available for sensitive strains.- Associated with more neuropsychiatric side effects.*Incorrect Option: Artesunate*- **Artesunate** is an **artemisinin derivative**, primarily used for severe malaria or in areas with **multi-drug resistant P. falciparum**.- While effective, it is not the preferred first-line agent for chloroquine-sensitive P. vivax due to the availability of simpler, equally effective treatments.- Typically used in combination therapy (ACT) for resistant strains.*Incorrect Option: Quinine*- **Quinine** is an older antimalarial, often used for **severe malaria** or in cases of **chloroquine-resistant P. falciparum**.- It has a higher incidence of side effects compared to chloroquine (cinchonism, hypoglycemia) and is not the preferred choice for chloroquine-sensitive P. vivax.- Requires longer treatment duration with more monitoring.
Question 103: What is the recommended therapeutic supplementation of iron and folic acid for adults with deficiency?
- A. 20 mg iron, 500 mcg folic acid
- B. 40 mg iron, 250 mcg folic acid
- C. 100 mg iron, 500 mcg folic acid (Correct Answer)
- D. 100 mg iron, 100 mcg folic acid
Explanation: ***100 mg iron, 500 mcg folic acid*** - For adults with **iron deficiency anemia**, the therapeutic dose of elemental iron is typically **100-200 mg daily**, commonly given as ferrous sulfate 325 mg (containing ~65 mg elemental iron) 2-3 times daily. **100 mg is an appropriate therapeutic dose**. - For **folic acid deficiency**, the standard therapeutic dose is **1-5 mg (1000-5000 mcg) daily** for treating established deficiency. However, **500 mcg (0.5 mg)** represents a minimal therapeutic/high prophylactic dose that may be used in milder deficiencies or as initial supplementation. Among the given options, this is the most appropriate combination. *20 mg iron, 500 mcg folic acid* - **20 mg of iron** is grossly insufficient for therapeutic supplementation in iron deficiency anemia and would fail to correct the anemia adequately. - While 500 mcg folic acid has some therapeutic value, the **iron dose is far too low** for treatment. *40 mg iron, 250 mcg folic acid* - **40 mg of iron** is a prophylactic dose (used in pregnancy or prevention) but is **insufficient for therapeutic correction** of established iron deficiency anemia. - **250 mcg of folic acid** is also a prophylactic dose and inadequate for treating established deficiency. *100 mg iron, 100 mcg folic acid* - **100 mg of iron** is an appropriate therapeutic dose for treating **iron deficiency anemia**. - However, **100 mcg of folic acid** is purely a maintenance/prophylactic dose found in multivitamins and is **grossly insufficient** for treating established folic acid deficiency.
Question 104: Best method of treatment for methyl alcohol poisoning is:
- A. Calcium gluconate
- B. Ethyl alcohol (Correct Answer)
- C. Amphetamines
- D. 1% Ammonia
Explanation: ***Ethyl alcohol*** - **Ethanol** (ethyl alcohol) acts as a competitive substrate for **alcohol dehydrogenase**, the enzyme responsible for metabolizing **methanol** into toxic metabolites like formaldehyde and formic acid. - By saturating alcohol dehydrogenase, ethanol prevents the formation of these toxic metabolites, allowing methanol to be excreted unchanged. - **Clinical note**: While **fomepizole** (4-methylpyrazole) is now the preferred first-line antidote when available, **ethanol** remains an effective and widely used alternative, especially in resource-limited settings. - **Administration**: IV ethanol is given to maintain blood ethanol concentration of 100-150 mg/dL. *Calcium gluconate* - **Calcium gluconate** is primarily used to treat **hypocalcemia**, ethylene glycol poisoning (for hypocalcemia), or hydrofluoric acid burns. - It has no role in the management of methyl alcohol poisoning as it does not interfere with the metabolism of methanol or its toxic byproducts. *Amphetamines* - **Amphetamines** are central nervous system stimulants used for conditions like ADHD and narcolepsy. - They have no therapeutic benefit or antidotal properties in the context of methanol poisoning. *1% Ammonia* - **Ammonia** is a strong base and is highly corrosive; it has no medical application as an antidote for methanol poisoning. - Administering ammonia would cause direct tissue damage and exacerbate patient harm due to its toxic and caustic properties.
Question 105: When alcohol is consumed with aerated soft drinks -
- A. Effect is enhanced
- B. To reduce hangover risk
- C. Absorption is faster, increasing intoxication risk (Correct Answer)
- D. None of the options
Explanation: ***Absorption is faster, increasing intoxication risk*** - The carbonation in aerated soft drinks speeds up the absorption of alcohol into the bloodstream. - This **faster absorption** leads to a more rapid increase in blood alcohol concentration and can intensify the effects of alcohol, thereby increasing the risk of intoxication. *Effect is enhanced* - While the **effect** might seem to be enhanced due to quicker onset, this option doesn't fully explain the physiological mechanism. - The primary reason for the perceived enhancement is the **accelerated absorption**, not a direct potentiation of alcohol's action. *To reduce hangover risk* - Mixing alcohol with aerated drinks generally **does not reduce hangover risk**; in fact, the rapid absorption can sometimes worsen dehydration and lead to a more severe hangover. - Hangovers are primarily caused by dehydration, acetaldehyde buildup, and other congeners, which are not mitigated by carbonated mixers. *None of the options* - This option is incorrect because the statement about **faster absorption leading to increased intoxication risk** is a well-established physiological effect.
Question 106: From which part of the Papaver somniferum plant does the latex, commonly referred to as 'milk', exude?
- A. Leaf of the plant
- B. Root of the plant
- C. Seeds of the plant
- D. Unripe capsule of the plant (Correct Answer)
Explanation: ***Unripe capsule of the plant*** - The **latex** (or 'milk') containing **opioid alkaloids** like morphine and codeine is primarily harvested by incising the **unripe seed capsules** of the *Papaver somniferum* plant. - This milky sap is then collected and dried to produce **crude opium**. *Leaf of the plant* - The leaves of *Papaver somniferum* do not contain significant amounts of the latex and are not the primary source of **opium alkaloids**. - While some **alkaloids** might be present in trace amounts, they are not extracted commercially from the leaves. *Root of the plant* - The roots of the poppy plant are not known to exude latex or to be a significant source of medically relevant **opioid alkaloids**. - Their primary function is absorption of water and nutrients, and anchoring the plant. *Seeds of the plant* - While the dried seeds are used for culinary purposes (poppy seeds), they contain very low levels of **opioid alkaloids** compared to the latex. - The latex is produced within the **capsule** before the seeds fully mature.
Question 107: Which of the following substances is commonly known as an arrow poison used by indigenous South American tribes?
- A. Opium
- B. Curare (Correct Answer)
- C. Cannabis
- D. Cyanide
Explanation: ***Curare*** - **Curare** is the traditional name for South American arrow poisons derived from plants, primarily *Chondrodendron tomentosum* and *Strychnos* species - It acts as a **competitive non-depolarizing neuromuscular blocking agent**, blocking nicotinic receptors at the neuromuscular junction - Causes **skeletal muscle paralysis** by competing with acetylcholine, leading to respiratory failure in prey - **Clinical relevance:** Tubocurarine (d-tubocurarine), derived from curare, was historically used as a muscle relaxant in surgery; modern derivatives include atracurium, vecuronium, and rocuronium *Opium* - **Opium** is derived from *Papaver somniferum* (opium poppy) and contains alkaloids like morphine and codeine - Acts on **opioid receptors** in the CNS to produce analgesia and sedation - Not used as an arrow poison by South American tribes; its effects are analgesic rather than paralytic *Cannabis* - **Cannabis** (*Cannabis sativa*) contains psychoactive compounds like THC (tetrahydrocannabinol) - Acts on **cannabinoid receptors** producing psychoactive and analgesic effects - Not used as an arrow poison; lacks the rapid paralytic action needed for hunting *Cyanide* - **Cyanide** inhibits cytochrome c oxidase, blocking cellular respiration and causing rapid cell death - While highly toxic, it is **not the traditional arrow poison** of South American indigenous tribes - Traditional arrow poisons like curare cause neuromuscular paralysis rather than cellular asphyxiation
Question 108: In the context of pharmacology, what is the term 'Mickey Finn' commonly associated with?
- A. Chloroform
- B. Methyl alcohol
- C. Chloral hydrate (Correct Answer)
- D. Ethylene glycol
Explanation: ***Chloral hydrate*** - A "Mickey Finn" is a slang term for a drink **laced with a psychoactive drug or incapacitating agent** given to an unsuspecting person. - Historically, **chloral hydrate** was a common substance used for this purpose due to its rapid sedative-hypnotic effects. *Chloroform* - While chloroform is a potent anesthetic and sedative, it is primarily used as an **inhalant** and is not typically administered orally in drinks. - Ingesting chloroform in large quantities can be **fatal due to severe hepatotoxicity and neurotoxicity**. *Methyl alcohol* - **Methyl alcohol (methanol)** is highly toxic and causes severe metabolic acidosis, blindness, and death, even in small amounts. - It does not induce the quick, incapacitating sedative effects associated with a "Mickey Finn" but rather a **delayed, severe poisoning syndrome**. *Ethylene glycol* - **Ethylene glycol** is an antifreeze agent that is also highly toxic, causing kidney failure and metabolic derangements. - Similar to methanol, its effects are **delayed and severe**, not the immediate incapacitating sedation implied by the term "Mickey Finn."
Question 109: Digitalis is used in mitral stenosis to control the ventricular rate when the patient develops which condition?
- A. Atrial fibrillation (Correct Answer)
- B. Right ventricular failure
- C. Acute pulmonary edema
- D. Myocarditis
Explanation: ***Atrial fibrillation*** - **Digitalis** (digoxin) is effective in **slowing the ventricular rate** in atrial fibrillation by increasing vagal tone and prolonging the refractory period of the AV node. - In **mitral stenosis**, an uncontrolled rapid ventricular rate due to atrial fibrillation can significantly reduce cardiac output and worsen symptoms. *Right ventricular failure* - While digitalis can improve contractility, its primary role in **RV failure** is not rate control; diuretics and afterload reduction are more commonly used. - A patient with isolated right ventricular failure due to mitral stenosis would not directly benefit from digitalis for rate control. *Acute pulmonary edema* - **Acute pulmonary edema** requires rapid diuresis, oxygen, and vasodilators to reduce preload and afterload. - Digitalis has a slower onset of action and is not the first-line treatment for acute pulmonary edema, especially if the cause is not related to a rapid ventricular rate. *Myocarditis* - **Myocarditis** is an inflammation of the heart muscle, and digitalis is generally avoided due to concerns about potentially worsening arrhythmias and myocardial damage in an inflamed heart. - Treatment for myocarditis focuses on supportive care and addressing the underlying cause, not rate control with digitalis unless specific arrhythmias develop.
Question 110: All of the following are characteristic features of treatment of iron deficiency anemia with oral iron supplements, except which of the following?
- A. Bioavailability is enhanced with vitamin C
- B. The proportion of iron absorbed reduces as hemoglobin improves
- C. The reticulocyte count should begin to increase within 7-10 days and peak at 2-4 weeks; this suggests good response to treatment
- D. The treatment should be discontinued immediately once hemoglobin normalizes to prevent side effects of iron (Correct Answer)
Explanation: ***The treatment should be discontinued immediately once hemoglobin normalizes to prevent side effects of iron*** - Treatment of **iron deficiency anemia** with oral iron supplements should continue for at least **3-6 months** after hemoglobin normalizes to replenish **iron stores**. - Premature cessation can lead to a rapid **recurrence of anemia** due to depleted iron reserves, despite normal hemoglobin levels. *Bioavailability is enhanced with vitamin C* - **Ascorbic acid (vitamin C)** creates an acidic environment in the stomach and reduces ferric iron (Fe3+) to ferrous iron (Fe2+), which is more readily absorbed. - This enhancement of **ferrous iron absorption** is a common practice to improve the efficacy of oral iron supplements. *The proportion of iron absorbed reduces as hemoglobin improves* - The body's **iron absorption mechanism** is tightly regulated by **hepcidin**, a hormone that increases when iron stores are sufficient. - As hemoglobin levels improve and iron stores are replenished, hepcidin levels rise, leading to a **decrease in iron absorption** to prevent iron overload. *The reticulocyte count should begin to increase in two weeks and peak in 4 weeks this suggests good response to treatment* - An increase in **reticulocyte count** by approximately **7-10 days** and peaking around **2-4 weeks** after starting iron therapy indicates that the bone marrow is effectively responding to the increased iron availability by producing new red blood cells. - This **reticulocytosis** is an early and reliable sign of a positive treatment response before a significant rise in hemoglobin is observed.