21st May 2025

A 73-year-old patients presents in status epilepticus, with no background of epilepsy and no history of head injury.

A 73-year-old patients presents in status epilepticus, with no background of epilepsy and no history of head injury. CT head is normal, and bloods shows a sodium of 113, potassium of 3.3. They had a blood test with their GP 2 days ago as part of a routine thyroid screen, which was normal. 

In patients with an acute onset (<48 hours), symptomatic hyponatraemia and euvolaemia, which of the following is true? Please select only ONE answer.