MRCP2-0842

A 50-year-old, previously healthy construction worker presents to the hospital with difficulty breathing. He also reports experiencing nausea, vomiting, and diarrhea. During the physical exam, the patient displays widespread expiratory polyphonic wheezing and muscle fasciculations. His wife reports that he has been working on a construction site for the past two days. Upon examination, the patient’s pupils are constricted bilaterally, and his blood pressure is 95/50 mmHg with a heart rate of 38 bpm. Which medication is most likely to provide the greatest benefit?