MRCP2-0916

A 30-year-old woman presents to the ED with a sudden onset rash. She reports feeling fatigued lately with a sore throat and cough. She is a smoker of 10 cigarettes/day.

During the examination, the patient has multiple painful erosions on the inside of her lips, an inflamed throat, and diffuse wheezing. On her palms and forearms, she has several swollen papules, some of which have small blisters in the center, forming a target-like lesion.

What is the most probable trigger for her condition?