Central pontine and extrapontine myelinolysis (CPEM) are recognised complications of hyponatraemia and its overly rapid correction.1 CPEM usually presents with spastic tetraparesis and pseudobulbar palsy.1 We describe a patient with CPEM in whom behavioural manifestations overshadowed corticospinal tract signs.

A 64 year old Chinese speaking woman with a history of episodic psychotic depression that had never required admission to hospital was admitted to a hospital because of vomiting and diarrhoea. Her general and neurological examination were normal. On admission she had a sodium concentration of 105 meq /l. An infusion of 3% saline at a rate of 150 ml/ hour was given during 6 hours. Ten hours later her sodium was 134 meq/l and she …