A 17-year-old girl is brought to the emergency department 15 minutes after being stung by a bee. She has mild light-headedness but no difficulty swallowing. Her temperature is 37.1°C (98.8°F), pulse i

A 17-year-old girl is brought to the emergency department 15 minutes after being stung by a bee. She has mild light-headedness but no difficulty swallowing. Her temperature is 37.1°C (98.8°F), pulse is 100/min, respirations are 30/min, and blood pressure is 115/70 mmHg. Physical examination shows no urticaria. Bilateral wheezing is heard on auscultation of the chest. Which of the following types of drugs is the most appropriate pharmacotherapy for this patient?