One of us (Rogen, 1957) has reported a patient in whom extensive cardiographic abnormalities were associated with massive urticaria, the abnormalities being of short duration and clearing with rapid recovery from the urticaria. Her condition is summarized shortly as Case 2. The first patient reported here as Case 1 had associated mild urticaria only, but the electrocardiogram showed features similar to those previously reported by others. We have been given notes about another patient (Case 3), similar except that the cardiographic changes lasted for longer. Case 1. A young man, aged twenty-one, had been ill since he had eaten a sandwich made with tinned pilchards. Six hours after eating the sandwich he developed severe generalized abdominal pain, which lasted until the following morning: there was occasional vomiting and diarrhoea in the form of two to three loose, normally coloured, stools in the day for the five days until he was admitted to hospital. Shortly after the onset of the abdominal pain he felt "a gripping pain" in the left mammary region radiating down the inner aspect of both arms to the elbows, the pain lasting about ten minutes at a time and recurring roughly every three hours. This type of pain was troublesome for the first three days of his illness, but for the two days before his admission it alternated with two attacks of severe bilateral constricting chest pain lasting up to 13 hours. With the second attack of severe long-lasting pain he felt dizzy and weak and sweated. It was shortly after the cessation of this attack of pain that he was admitted to Ruchill Hospital. He gave no history of recent cold, sore throat, or joint pains.He was a well-built young man who indulged in boxing and swimming without chest pain or other ill effects. There was no history of recent injections or of drug taking and no history of any skin rash following the taking of medicines in the past. One sister, aged 17, had psoriasis but there was no history of allergic disease in the patient, his parents, or his two sisters. The patient had no diarrhoea or chest pain while in hospital. He was not dehydrated. He had a mild urticarial eruption on the back of his chest which cleared within three days. There was no triple rhythm or other significant abnormality on clinical examination of the heart. His blood pressure was labile and was most commonly around 120/70 mm. Hg. Two specimens of stool were negative for intestinal pathogenic organisms. Haemoglobin, white blood count, and differential white blood count were within normal limits, and no abnormality was found in the urine or on radiological examination of heart or lungs.A cardiogram taken on admission showed changes compatible with antero-lateral ischiemic heart damage ( Fig. 1): that taken three days later was normal (Fig. 2). No drug treatment was given.The only evidence of an allergic reaction in this patient was the fine urticarial eruption noted on his back; this cleared rapidly after his admission to hospital and was absent when the second cardiogram was taken...