WBR0678
| Author | [[PageAuthor::Rim Halaby, M.D. [1]]] |
|---|---|
| Exam Type | ExamType::USMLE Step 1 |
| Main Category | MainCategory::Pharmacology |
| Sub Category | SubCategory::Pulmonology |
| Prompt | [[Prompt::An 8 year old boy, with a past medical history of asthma, is brought to the emergency department (ED) for seizures, severe abdominal pain, and vomiting. Upon further questioning, his parents explain that they traveled to USA one day before admission and a new asthma medication has been very recently prescribed by a physician abroad. His vital signs show tachycardia. Work-up shows major electrolyte disturbances, including hypokalemia, hypophosphatemia, hypomagnesemia, and hypocalcemia. The ED physician explains to the parents that the children must have been taken very high doses of his asthma medication. Which of the following medications should be prescribed to reverse the patient's condition?]] |
| Answer A | AnswerA::Esmolol |
| Answer A Explanation | AnswerAExp::Esmolol is a beta-blocker that is effective for theophylline toxicity. |
| Answer B | AnswerB::Nicardipine |
| Answer B Explanation | AnswerBExp::Nicardipine is a calcium channel blocker that is not usually used as antidote. |
| Answer C | AnswerC::Glucagon |
| Answer C Explanation | AnswerCExp::Glucagon may be used as antidote for beta-blocker toxicity. |
| Answer D | AnswerD::Flumazenil |
| Answer D Explanation | AnswerDExp::Flumazenil may be used as antidote for benzodiazepine toxicity. |
| Answer E | AnswerE::Atropine |
| Answer E Explanation | AnswerEExp::Atropine may be used as antidote for organophosphate and acetylcholinesterase inhibitor toxicity. |
| Right Answer | RightAnswer::A |
| Explanation | [[Explanation::The patient is presenting with signs and symptoms consistent with theophylline toxicity due to overdose in his theophylline, which is used to treat his asthma. Theophylline induces the release of catecholamines to stimulate the B-adrenergic receptors. It causes systemic symptoms, such as seizures, vomiting, abdominal pain, marked tachycardia, and electrolyte disturbances, such as those observed in the patient in the vignette. The final outcome in severe overdose is cardiovascular collapse and death. B-blockers are used as antidotes for management of theophylline toxicity. Esmolol, a beta-1-selective adrenergic receptor antagonist with a short duration of action, is has been used in emergency situations as a choice of B-blockers. Educational Objective: |
| Approved | Approved::No |
| Keyword | WBRKeyword::esmolol, WBRKeyword::beta, WBRKeyword::blocker, WBRKeyword::blockers, WBRKeyword::theophylline, WBRKeyword::overdose, WBRKeyword::toxicity, WBRKeyword::vomiting, WBRKeyword::abdominal, WBRKeyword::pain, WBRKeyword::seizure, WBRKeyword::adrenergic, WBRKeyword::receptor, WBRKeyword::antagonist, WBRKeyword::antagonism |
| Linked Question | Linked:: |
| Order in Linked Questions | LinkedOrder:: |