What is the treatment for hypermagnesemia?

From the Guidelines

The treatment for hypermagnesemia should prioritize stopping magnesium intake, enhancing elimination, and managing symptoms, with intravenous calcium gluconate being a crucial intervention for severe cases or cardiac manifestations, as supported by the 2015 American Heart Association guidelines update for cardiopulmonary resuscitation and emergency cardiovascular care 1.

Key Interventions

• Discontinue all magnesium-containing medications, supplements, and antacids to halt further magnesium intake.
• Use intravenous fluids with normal saline to dilute and excrete excess magnesium through the kidneys.
• Consider loop diuretics like furosemide (20-40mg IV) to increase urinary magnesium excretion.
• For severe hypermagnesemia or cardiac manifestations, administer intravenous calcium gluconate (1-2g IV over 5-10 minutes) as a physiological antagonist to magnesium, as recommended in the context of cardiac arrest associated with hypermagnesemia 1.

Special Considerations

• In cases of renal failure or severe hypermagnesemia (>7 mg/dL), hemodialysis is the most effective treatment to rapidly remove magnesium from the bloodstream.
• Supportive care should address any cardiac arrhythmias, hypotension, or respiratory depression.
• The underlying cause of hypermagnesemia should be identified and addressed to prevent recurrence.
• Treatment effectiveness can be monitored through serum magnesium levels, electrocardiogram findings, and improvement in clinical symptoms like deep tendon reflexes and mental status.

Evidence Basis

The recommendation for using calcium in the treatment of hypermagnesemia, especially in the context of cardiac arrest, is supported by guidelines from the American Heart Association, such as those outlined in the 2010 and 2015 updates for cardiopulmonary resuscitation and emergency cardiovascular care 1. However, the most recent and highest quality guideline from 2015 1 provides the basis for the current recommendation, emphasizing the role of calcium administration in managing cardiac arrest associated with hypermagnesemia.

From the Research

Treatment of Hypermagnesemia

The treatment of hypermagnesemia involves several approaches, including:

• Discontinuing magnesium-containing therapies 2
• Intravenous fluid therapy to help reduce magnesium levels 2, 3, 4
• Administration of calcium preparations, such as calcium gluconate, to counteract the effects of excess magnesium 3, 4, 5
• Use of loop diuretics to enhance magnesium excretion 3, 4
• Dialysis in severe cases to rapidly correct magnesium levels 2, 4, 5
• Continuous renal replacement therapy (CRRT) as an alternative to dialysis in some cases 5

Management Strategies

Management of hypermagnesemia also involves:

• Prompt identification and monitoring of serum magnesium concentration in patients at risk of hypermagnesemia 2
• Preventing hypermagnesemia by avoiding magnesium-containing medications or supplements in high-risk populations, such as patients with impaired renal function 2
• Exercise caution when prescribing Epsom salts to patients with underlying gastrointestinal conditions 5
• Consideration of alternative drug therapies to mitigate the risk of hypermagnesemia 5

Supportive Care

Supportive care for patients with hypermagnesemia may include:

• Symptomatic treatment, such as management of respiratory and cardiovascular complications 3
• Monitoring for signs of neuromuscular dysfunction, such as weakness and decreased reflexes 3, 4
• Management of gastrointestinal symptoms, such as constipation and abdominal distension 3