Presentation of Case The patient was a 78 year old man,who had been coming to the outpatient clinic for some time. He had cardiac failure, which was controlled on digoxin and diuretics, the doses of which had been adjusted from time to time over the years. At one visit the dose of digoxin was increased to 0.125mg daily; the diuretic treatment was hydrochloro-thia-zide 25 mg daily. He was taking noother drugs. When he was seen by the consultant in outpaitents at the next visit he gave Presentation of Case The patient was a 78 year old man, who had been coming to the outpatient clinic for some time. He had cardiac failure, which was controlled on digoxin and diuretics, the doses of which had been adjusted from time to time over the years. At one visit the dose of digoxin increased to 0.125 mg daily; the diuretic treatment was hydrochloro-thia-zide 25 mg daily. He was taking noother drugs. When he was seen by the consultant in outpaitents at the next visit he gave