A 25 year old patient is diagnosed with genital herpes simplex virus infection. * Which of the following drug would be most appropriate to prescribe in treating this patient's illness?

Correct Answer: C

Rationale: The correct answer is C: Valacyclovir. Valacyclovir is an antiviral medication commonly used to treat herpes simplex virus infections. It is a prodrug of acyclovir, which inhibits viral DNA replication. Zanamivir (A) is used to treat influenza viruses, not herpes. Lamivudine (B) is used for HIV and hepatitis B, not herpes. Cidofovir (D) is used for cytomegalovirus and other viral infections, but not the first line for herpes. Valacyclovir is the most appropriate choice due to its effectiveness and safety profile in treating herpes simplex virus infections.

Correct Answer: A

Rationale: Rationale: 1. Piperazine is the correct answer as it acts as a cholinergic agonist in nematodes, causing spastic paralysis by mimicking acetylcholine. 2. Pyrantel pamoate works by depolarizing neuromuscular junctions, not through cholinergic agonism. 3. Mebendazole and Albendazole inhibit microtubule synthesis in worms, leading to impaired glucose uptake, not cholinergic effects.

Correct Answer: D

Rationale: The correct answer is D because using antibiotic combinations covering both gram positive and gram negative bacteria can disrupt the balance of normal flora in the body, leading to superinfections. This is due to the broad spectrum of activity of these antibiotics, which can kill off a wider range of bacteria, including the beneficial ones. Choice A is incorrect because narrow spectrum antibiotics target specific types of bacteria, reducing the likelihood of disrupting the normal flora and causing superinfections. Choice B is incorrect because longer courses of antibiotics increase the risk of superinfections as they continue to disrupt the normal flora over a longer period. Choice C is incorrect because antibiotics that are completely absorbed from the small intestines do not necessarily increase the risk of superinfections; it is more about the spectrum of activity and the impact on normal flora.

Correct Answer: A

Rationale: Thiazide diuretics decrease urinary excretion of uric acid, leading to increased blood levels. Thiazides also increase potassium reabsorption, potentially causing hyperkalemia. However, the main effect on uric acid levels makes choice A correct. Choices B, C, and D are incorrect as thiazides do not directly impact BUN, urea, or glucose levels.

Correct Answer: D

Rationale: The correct answer is D: Conivaptan. Conivaptan is a non-peptide competitive antagonist of ADH, specifically targeting the V2 receptors in the collecting ducts of the nephron. This mechanism of action inhibits ADH's water-sparing effects, making it an effective treatment for SIADH. A: Mannitol is an osmotic diuretic used for conditions like cerebral edema and acute kidney injury, not specifically for SIADH. B: Bumetanide is a loop diuretic used for conditions like heart failure and hypertension, not for managing SIADH. C: Spironolactone is a potassium-sparing diuretic used for conditions like heart failure and hypertension, not for treating SIADH. In summary, Conivaptan is the correct choice for managing SIADH due to its specific mechanism of action as a competitive antagonist of ADH in the collecting ducts, while the other options are