WBR0942

Author	PageAuthor::William J Gibson
Exam Type	ExamType::USMLE Step 1
Main Category	MainCategory::Pharmacology
Sub Category	SubCategory::Neurology
Prompt	[[Prompt::A 33-year-old woman presents to urgent care for a very painful headache. She recalls that prior to the onset of the headache, she experienced a bilateral loss of peripheral visual fields. She describes the pain as throbbing and localized to the frontotemporal areas. What is the mechanism of action of the most appropriate pharmacotherapy?]]
Answer A	AnswerA::5-HT 1B/1D agonist
Answer A Explanation	AnswerAExp::Correct: Sumatriptan is a serotonin analogue that acts as a 5-HT 1B/1D agonist to relieve migraine headaches.
Answer B	AnswerB::5-HT 3 antagonist
Answer B Explanation	AnswerBExp::This describes Ondansetron, an anti-emetic used in conjunction with chemotherapy. Ondansetron is not effective in treating migraine headaches.
Answer C	AnswerC::Cyclooxygenase inhibitor
Answer C Explanation	AnswerCExp::Incorrect: This is the mechanism of action of NSAIDs. While NSAIDs may be used to treat headaches, an acute migraine is more appropriately treated with sumatriptan.
Answer D	AnswerD::Potentiate GABA by increasing the frequency of Cl channel opening
Answer D Explanation	AnswerDExp::Incorrect: This describes the mechanism of action of benzodiazepines, which are not effective for the treatment of migraine headaches.
Answer E	AnswerE::Phosphodiesterase inhibitor
Answer E Explanation	AnswerEExp::Incorrect: This describes the mechanism of action of sildenafil. One side effect of sildenafil is headache.
Right Answer	RightAnswer::A
Explanation	[[Explanation:: Educational Objective: References: ]]
Approved	Approved::Yes
Keyword	WBRKeyword::Headache, WBRKeyword::Migraine, WBRKeyword::Migraine headache, WBRKeyword::Serotonin, WBRKeyword::5-HT, WBRKeyword::Mechanism
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Order in Linked Questions	LinkedOrder::