Table 1: Causes of hypokalaemia.

Urinary losses
 Diuretics
 Hypomagnesaemia
 Bartter and Gitelman syndromes
Gastrointestinal losses
 Vomiting
 Diarrhoea or laxative abuse
Decreased potassium intake
 Poor oral intake
Hyperaldosteronism
 Primary hyperaldosteronism
 Secondary hyperaldosteronism
 Others (e.g. excessive liquorice intake)
Shift of potassium into cells
 Metabolic alkalosis
 Excessive insulin
 Hypo/hyperkalaemic periodic paralysis
 Thyrotoxic periodic paralysis
 Adrenergic stimulation (e.g. beta-agonists or
 phaeochromocytoma)
Others
 Liddle syndrome
 Ectopic adrenocorticotrophic hormone