Scombroid fish or histamine food poisoning is an illness typically associated with fish consumption, rarely encountered and reported in Europe. Symptoms develop quickly and resemble an allergic reaction. This paper reports three cases of severe scombroid poisoning in previously healthy patients, which presented diffuse macular erythema, hypotension, palpitations, and abnormal electrocardiogram (ECG). All patients required intensive care, with a complete resolution of symptoms and ECG changes within 24 hours. This is the first Romanian report of scombroid poisoning, emphasizing that medical personnel should be aware of this condition, because symptoms and ECG changes often lead to confusion with other diseases.