Hypomagnesaemia in elderly digitalised patients.

Hypomagnesaemia and hypokalaemia are known to predispose to digoxin toxicity. Elderly patients receiving diuretics may be at special risk. A 12-month survey of all patients receiving digoxin at the time of admission to our Geriatric Assessment Unit revealed 16% were hypomagnesaemic, whereas no patient was hypokalaemic. There is a need for greater awareness of the risk of magnesium depletion in elderly patients receiving concurrent diuretic and digoxin therapy.