A2-year-old boy was brought to the emergency department with high body temperature (104°F, 40°C), flushed and dry skin, and widely dilated pupils unresponsive to light. He was agitated and underwent a brief tonic-clonic convulsion. His mother stated that the boy apparently swallowed several tablets of her allergy medication. Which of the following drugs most likely caused the patient's poisoning?

Correct Answer: B

Rationale: The correct answer is B: Diphenhydramine. Diphenhydramine is a first-generation antihistamine that can cause anticholinergic toxicity in overdose. The symptoms described in the question such as high body temperature, dry skin, dilated pupils, and agitation are consistent with anticholinergic poisoning. Diphenhydramine also has sedative effects which can lead to seizures in high doses. A: Ibuprofen is a nonsteroidal anti-inflammatory drug and overdose typically presents with symptoms like gastrointestinal upset and kidney injury, not the symptoms described in the question. C: Phenylephrine is a decongestant that can cause hypertension and tachycardia in overdose, not the symptoms described in the question. D: Celecoxib is a selective COX-2 inhibitor used as an NSAID and overdose usually presents with gastrointestinal symptoms, not the symptoms described in the question.

Correct Answer: C

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

Correct Answer: A

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

Correct Answer: A

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

Correct Answer: D

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