Acute generalized exanthematous pustulosis (AGEP) is a rare, pustular rash that occurs most commonly after exposure to a medication (typically antibiotics or diltiazem). This case describes a patient who developed a widespread pustular eruption shortly after beginning empiric antibiotics for community-acquired pneumonia. Diagnosis of AGEP was difficult in this scenario due to the patient's pulmonary infection and atypical skin biopsy results. However, after AGEP was correctly identified, the offending agents were discontinued and the patient had subsequent resolution of her symptoms.