MSRA-1008

A 25-year-old man presents to the emergency department after consuming a cake containing hazelnut chocolate spread. He has a known allergy to tree nuts and has previously been hospitalized due to an anaphylactic reaction.

Upon examination, he displays a widespread, confluent erythematous urticarial rash at flexor sites. He is speaking in full sentences and has no signs of oral or peri-oral edema. There is no audible wheeze.

His vital signs indicate a respiratory rate of 22 breaths/min, 98% oxygen saturation in room air, a heart rate of 115 beats/min, and a blood pressure of 97/68 mmHg.

What is the most appropriate initial management for this patient?