- Hypokalaemia is a common electrolyte disorder in children, caused by decreased potassium intake, increased gastrointestinal and urinary losses or transcellular shift. Patients with severe hypokalaemia may suffer from symptoms such as life-threatening cardiac arrhythmias. The aim of our paper was to review the aetiology of hypoalaemia, suggest a diagnostic algorithm and discuss the management of patients with various aetiologies of hypokalaemia. Understanding the pathophysiology of hypokalaemic states, along with a detailed medical history, physical examination and specific laboratory tests, are required for proper diagnosis and appropriate treatment. This article is protected by copyright. All rights reserved.