Beta Blockers USMLE Step 1 Practice Question
A 52-year-old pesticide worker exposed to organophosphate presents with excessive salivation, wheezing, and marked skeletal muscle weakness with visible fasciculations. Vital signs show HR 58 bpm, BP 102/64 mmHg, RR 16/min, SpO2 98% on room air. After atropine administration, salivation and bronchospasm resolve, but muscle weakness persists. Serum cholinesterase activity is markedly decreased at 35% of normal. Pupillary constriction remains unchanged. Which medication most directly reverses the enzyme inhibition causing these persistent neuromuscular findings?
Answer choices
- AScopolamine
- BEdrophonium
- CPralidoximeCorrect answer
- DSuccinylcholine
- EPilocarpine
- FPhysostigmine
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