03-09-2008, 10:46 AM
A 24-year-old woman comes to the emergency department because of the acute onset of
abdominal cramping and hives in the previous 12 hours. She states that 2 days ago she
experienced a bad sore throat and took some leftover trimethoprim-sulfamethoxazole, along
with an over-the-counter cold medicine, which contained acetaminophen, diphenhydramine,
and pseudoephedrine, and several doses of aspirin. She has a history of asthma that is
exacerbated with upper respiratory infections, so she tried to treat herself before the asthma
was triggered. Otherwise, her medical history is significant for allergy to peanuts and
chocolate, which she avoids meticulously. Review of systems reveals a generalized itch that is
unbearable, and abdominal cramping of moderate degree. The patient denies difficulty
swallowing or breathing. On physical examination, she is in mild distress. Her blood pressure
is 105/65 mmHg, pulse is 90/min, and respirations are 24/min. Body temperature is 36 C (96.8
F). Inspection reveals multiple 1- to 10-cm pink and white urticarial papules and plaques on the
trunk and proximal extremities. Her eyelids are edematous and the lower lip appears to be
slightly edematous as well. Which of the following is the most likely cause of the skin lesions?
A. Acetaminophen
B. Aspirin
C. Diphenhydramine
D. Pseudoephedrine
E. Trimethoprim-sulfamethoxazole
abdominal cramping and hives in the previous 12 hours. She states that 2 days ago she
experienced a bad sore throat and took some leftover trimethoprim-sulfamethoxazole, along
with an over-the-counter cold medicine, which contained acetaminophen, diphenhydramine,
and pseudoephedrine, and several doses of aspirin. She has a history of asthma that is
exacerbated with upper respiratory infections, so she tried to treat herself before the asthma
was triggered. Otherwise, her medical history is significant for allergy to peanuts and
chocolate, which she avoids meticulously. Review of systems reveals a generalized itch that is
unbearable, and abdominal cramping of moderate degree. The patient denies difficulty
swallowing or breathing. On physical examination, she is in mild distress. Her blood pressure
is 105/65 mmHg, pulse is 90/min, and respirations are 24/min. Body temperature is 36 C (96.8
F). Inspection reveals multiple 1- to 10-cm pink and white urticarial papules and plaques on the
trunk and proximal extremities. Her eyelids are edematous and the lower lip appears to be
slightly edematous as well. Which of the following is the most likely cause of the skin lesions?
A. Acetaminophen
B. Aspirin
C. Diphenhydramine
D. Pseudoephedrine
E. Trimethoprim-sulfamethoxazole