When tetany is associated with hypomagnesemia, it may respond transiently to calcium or potassium administration but is permanently relieved only by repletion of magnesium, typically given as a 10% magnesium sulfate solution (1 g/10 mL) IV, followed by oral magnesium salts (eg, magnesium gluconate 500 to 1000 mg orally 3 times a day).