A patient with chronic pain is prescribed tramadol. Tramadol works primarily by:

Correct Answer: B

Rationale: The correct answer is B: Increasing serotonin and norepinephrine in the brain. Tramadol is a synthetic opioid analgesic that acts by binding to mu-opioid receptors and also inhibiting the reuptake of serotonin and norepinephrine. This dual mechanism of action helps alleviate pain by enhancing the effects of these neurotransmitters in the brain. Choices A, C, and D are incorrect because tramadol primarily affects serotonin and norepinephrine levels rather than blocking opioid receptors, inhibiting dopamine reuptake, or decreasing substance P in the spinal cord.

Correct Answer: D

Rationale: The correct answer is D: Induction of powerful uterine contracture. Ergonovine is a uterotonic agent that works by stimulating uterine contractions, which helps control postpartum hemorrhage due to uterine atony. The drug acts directly on the smooth muscle of the uterus, leading to increased tone and decreased bleeding. A: Selective constriction of uterine arteries is incorrect because ergonovine primarily acts on the uterine muscle itself, not the blood vessels supplying the uterus. B: Endothelin release in the uterine vascular bed is incorrect as ergonovine does not directly affect endothelin release. C: Platelet aggregation in the uterine vascular bed is incorrect as ergonovine's action is not related to platelet aggregation but rather to uterine muscle contraction. In summary, the therapeutic effect of ergonovine in this patient is mediated by its ability to induce powerful uterine contr

Correct Answer: C

Rationale: The correct answer is C: Ergotamine. Ergotamine is known to cause vasoconstriction, leading to decreased blood flow to extremities, resulting in numbness and tingling. Ibuprofen is a nonsteroidal anti-inflammatory drug and does not typically cause numbness and tingling. Valproic acid is used for epilepsy and mood disorders. Propranolol is a beta-blocker used for hypertension and migraines but is not associated with numbness and tingling in extremities.

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: D

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