Editor,—I congratulate Dr Ahee and Dr Crowe on their excellent article on the treatment of hyperkalaemia in the emergency department.¹ I have one query. The authors advocate the use of calcium gluconate 10% for its stabilising influence on the myocardium. The Resuscitation Council (UK) however, recommend that calcium chloride 10% be used in the treatment of electromechanical dissociation attributable to hyperkalaemia. I am under the impression that calcium chloride is preferable to calcium gluconate in the treatment of hyperkalaemia on account of its greater bioavailability.