Which of the following viruses is most susceptible to acyclovir?: *

Correct Answer: A

Rationale: Acyclovir is a nucleoside analog that inhibits viral DNA replication by targeting viral DNA polymerase. Herpes simplex Type 1 virus is most susceptible to acyclovir because it is a DNA virus that requires viral DNA polymerase for replication. The drug is selectively activated by viral thymidine kinase in infected cells, leading to its antiviral activity. Herpes simplex Type 2, Varicella zoster, and other viruses do not possess the same susceptibility to acyclovir due to differences in their replication mechanisms.

Correct Answer: C

Rationale: Step 1: Clofazimine is the correct answer because it is known to suppress both lepra reaction and reversal reaction in leprosy treatment. Step 2: Dapsone is mainly used to treat leprosy but does not specifically target lepra reaction. Step 3: Rifampin is effective against leprosy but does not have a direct impact on lepra reactions. Step 4: Minocycline can be used in leprosy treatment but does not have the same dual action as clofazimine.

Correct Answer: D

Rationale: The correct answer is D: Acetazolamide. Acetazolamide is a diuretic that inhibits carbonic anhydrase enzyme, leading to increased excretion of bicarbonate ions, thus causing metabolic alkalosis correction and reducing edema. Digoxin (A) is used for heart failure, Spironolactone (B) is a potassium-sparing diuretic, and Dobutamine (C) is a beta-adrenergic agonist used for heart failure, none of which directly address metabolic alkalosis.

Correct Answer: B

Rationale: Step 1: Furosemide is a loop diuretic, known for its high potency in inhibiting the reabsorption of sodium and chloride in the loop of Henle. Step 2: This leads to significant diuresis, causing hypovolemia and subsequent hypotension. Step 3: Acetazolamide is a carbonic anhydrase inhibitor diuretic, not as potent as loop diuretics. Step 4: Spironolactone is a potassium-sparing diuretic, less likely to cause hypotension due to its mechanism of action. Step 5: Hydrochlorothiazide is a thiazide diuretic, less potent than loop diuretics like furosemide in causing hypovolemia and hypotension.

Correct Answer: D

Rationale: Spironolactone is a potassium-sparing diuretic, so combining it with another potassium-sparing diuretic like amiloride can lead to hyperkalemia. Chlorthalidone, a thiazide-like diuretic, can be synergistic with spironolactone. Furosemide, a loop diuretic, can counteract the potassium-sparing effects of spironolactone. Hydrochlorothiazide, a thiazide diuretic, can also lead to hypokalemia when combined with spironolactone. Therefore, the correct answer is D, as combining spironolactone with hydrochlorothiazide may increase the risk of potassium imbalance.