From the Guidelines
Hypermagnesemia should be treated by discontinuing magnesium intake, administering intravenous calcium gluconate, and enhancing magnesium elimination through intravenous fluids and loop diuretics, with hemodialysis considered in severe cases or renal failure. The treatment approach is focused on reducing serum magnesium levels and mitigating its physiological effects. According to the American Heart Association guidelines 1, calcium administration, such as calcium chloride or calcium gluconate, may be considered in cases of hypermagnesemia, particularly when associated with cardiac arrest.
The definition of hypermagnesemia, as stated in the guidelines 1, is a serum magnesium concentration >2.2 mEq/L, and its symptoms can range from muscular weakness and paralysis to cardiorespiratory arrest. The treatment strategy involves:
- Discontinuing any magnesium-containing medications or supplements
- Administering intravenous fluids with normal saline to dilute and excrete excess magnesium
- Using intravenous calcium gluconate (1-2 grams over 5-10 minutes) to temporarily antagonize magnesium's effects
- Loop diuretics like furosemide (20-40 mg IV) to increase magnesium excretion
- Hemodialysis for severe hypermagnesemia or in patients with renal failure
Supportive care should address any cardiac arrhythmias, hypotension, or respiratory depression, and continuous cardiac monitoring is essential in severe cases. Regular monitoring of serum magnesium levels is necessary to guide ongoing treatment. The most recent and highest quality study 1 supports the use of calcium administration in the management of hypermagnesemia, particularly in the context of cardiac arrest.
From the Research
Treatment Options for Hypermagnesemia
- Discontinuing magnesium-containing therapies is a crucial step in managing hypermagnesemia 2
- Intravenous fluid therapy can help improve symptoms of hypermagnesemia 3, 2, 4
- Administration of calcium preparations, such as calcium gluconate, can help counteract the effects of excess magnesium 3, 4
- Loop diuretics may be given as an adjunct to help reduce magnesium levels 3, 4
- In severe cases of hypermagnesemia, dialysis may be necessary to rapidly correct magnesium levels 2, 4
Prevention of Hypermagnesemia
- Monitoring serum magnesium concentration in patients at risk of hypermagnesemia is essential to prevent complications 2
- Preventing hypermagnesemia is crucial, particularly in high-risk populations, such as patients with impaired renal function or those receiving magnesium-containing medications or supplements 2
- Limiting daily magnesium intake can help prevent hypermagnesemia, especially in patients with chronic kidney disease 5
Management of Severe Hypermagnesemia
- Severe hypermagnesemia can occur in patients with normal renal function and constipation under MgO, and can improve with symptomatic treatment without hemodialysis 3
- In cases of severe hypermagnesemia, prompt initiation of treatment is necessary to avoid significant hemodynamic or respiratory compromise 4