Eight patients with life threatening hyperkalemia were treated in the intensive care unit over a period of 2 years. Serum potassium at admission was 7.1-11.2. Two patients had to be resuscitated and 3 exhibited quadriplegia or paralyses but were alert. Seven showed marked ECG change: in 5 the QRS-complexes were extremely broadened and in one case an AV-rhythm was observed; the atrial wave was absent in all 7 patients. Renal failure was present in 7 of 8 patients. In 6 of these 8 cases drugs were also involved in the development of hyperkalemia. The following therapeutic procedure is recommended for hyperkalemia: (1) injection of calcium, (2) inhalation or injection of beta 2-mimetics (well documented in the literature; clinical experience limited), (3) insulin and glucose i.v., (4) sodium bicarbonate, but only in case of metabolic acidosis, (5) hemodialysis, (6) cation exchange resins or furosemide in non-acute situations.