Histamine fish poisoning, also known as scombroid poisoning, is a histamine toxicity syndrome that results from eating specific types of spoiled fish. Although typically a benign syndrome, characterized by self-limited flushing, headache, and gastrointestinal symptoms, we describe a case unique in its severity and as a precipitant of an asthma exacerbation. A 25-year-old woman presented to the emergency department (ED) with one hour of tongue and face swelling, an erythematous pruritic rash, and dyspnea with wheezing after consuming a tuna sandwich. She developed abdominal pain, diarrhea and hypotension in the ED requiring admission to the hospital. A diagnosis of histamine fish poisoning was made and the patient was treated supportively and discharged within 24 hours, but was readmitted within 3 hours due to an asthma exacerbation. Her course was complicated by recurrent admissions for asthma exacerbations.