Tick the group of antibiotics having an antimalarial effect:

Correct Answer: B

Rationale: Step 1: Tetracyclins are known to have antimalarial properties by inhibiting protein synthesis in Plasmodium species. Step 2: Aminoglycosides (choice A) primarily target bacteria, not parasites like malaria. Step 3: Carbapenems (choice C) and Penicillins (choice D) are both beta-lactam antibiotics that have no significant antimalarial effects. Summary: Tetracyclins are the correct choice as they directly target malaria parasites, while the other options do not possess antimalarial properties.

Correct Answer: D

Rationale: The correct answer is D: Nitroprusside. Nitroprusside is a potent vasodilator that can rapidly induce controlled hypotension by relaxing smooth muscle in blood vessels. This helps in minimizing blood loss during surgery. Labetalol (A) is a non-selective beta-blocker with alpha-blocking activity, which may not provide rapid hypotension. Hydralazine (B) is a direct vasodilator that can cause reflex tachycardia and may not be as effective in controlled hypotension. Nifedipine (C) is a calcium channel blocker primarily used for hypertension but does not provide rapid hypotension like nitroprusside.

Correct Answer: D

Rationale: The correct answer is D: Prazosin. Prazosin is an alpha-1 adrenergic blocker that can cause orthostatic hypotension, leading to dizziness and fainting when standing up rapidly. It works by dilating blood vessels, which can cause a sudden drop in blood pressure upon standing. Propranolol (A) is a beta-blocker and can cause dizziness but is less likely to cause orthostatic hypotension. Minoxidil (B) is a vasodilator that can cause rapid heart rate but not typically dizziness upon standing. Hydralazine (C) is a direct vasodilator that can cause reflex tachycardia but is less likely to cause orthostatic hypotension compared to alpha-1 blockers like Prazosin.

Correct Answer: C

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.

Correct Answer: B

Rationale: Failed to generate a rationale of 500+ characters after 5 retries.