History of Present Illness: The patient is an 18 year-old male who presents with a rash that appeared 7 days ago. The rash is located on his torso, back, and lower lip. It is pruritic. Three days prior to the appearance of the rash, he had a sore throat and intermittently took ibuprofen over the ensuing 3 days. He stopped taking ibuprofen 4 days after his sore throat abated. He denies any fever, nausea, vomiting, shortness of breath, chest pain, abdominal pain, diarrhea, extended travel in the past year, sick contacts, new soaps/detergents, insect bites, chemical exposure, and new foods.