All of the following are examples of enteral routes of administration except

Correct Answer: A

Rationale: The correct answer is A: Intramuscular. Enteral routes involve administration through the gastrointestinal tract, such as oral, sublingual, and rectal. Intramuscular administration bypasses the GI tract, making it a parenteral route. Therefore, it is not an enteral route. Oral involves swallowing, sublingual is under the tongue, and rectal is through the rectum, all entering the GI tract for absorption.

Correct Answer: B

Rationale: The correct answer is B because physiologic changes in older adults affect all pharmacokinetic processes, leading to increased risk for drug reactions. These changes include decreased renal function, altered drug metabolism, reduced liver enzyme activity, and changes in body composition. Option A is incorrect because the blood-brain barrier remains intact with age. Option C is incorrect as older adults have decreased drug-metabolizing enzymes. Option D is incorrect because while immune response may decline with age, it is not the primary factor contributing to increased drug reactions in older adults.

Correct Answer: D

Rationale: The correct answer is D because mannitol is an osmotic diuretic that increases the osmolarity of plasma. This high osmolarity creates an osmotic pressure gradient that pulls water out of the tissues into the bloodstream, leading to increased urine production. Choice A is incorrect because mannitol does not compete with aldosterone for cellular receptor sites. Choice B is incorrect because mannitol primarily works in the proximal tubule, not the loop of Henle. Choice C is incorrect because mannitol does not interfere with the absorption of sodium ions across the distal renal tubule.

Correct Answer: A

Rationale: The correct answer is A because the half-life of naloxone is relatively short, typically around 30-81 minutes. This short half-life means that the effects of naloxone wear off quickly, necessitating repeated doses to maintain its therapeutic effects in reversing opioid overdose. Choice B is incorrect because an increase in dosage is not necessarily required due to the short half-life of naloxone. Choice C is incorrect because as long as naloxone is still effective in reversing opioid overdose, there is no need for a different antidote solely based on the decreasing serum levels of naloxone. Choice D is incorrect because naloxone is an effective antidote for opioid overdose when administered correctly, despite its short half-life.

Correct Answer: A

Rationale: The correct answer is A: Intravenous. In cardiovascular collapse, immediate action is crucial. Intravenous administration ensures rapid delivery of medications directly into the bloodstream, achieving quick onset of action. Oral route is too slow, rectal route may be unreliable, and topical route is not suitable for immediate systemic effects. Intravenous route is the most appropriate in this critical situation.