From the Guidelines
Magnesium overdose is a life-threatening condition that requires immediate medical attention, and treatment typically involves stopping magnesium intake, providing intravenous fluids, and in severe cases, administering calcium gluconate to counteract magnesium's effects. The symptoms of magnesium overdose can range from mild to severe and include nausea, vomiting, diarrhea, abdominal cramping, low blood pressure, irregular heartbeat, confusion, muscle weakness, difficulty breathing, and in extreme cases, cardiac arrest 1. People with kidney disease are at higher risk because they cannot efficiently eliminate excess magnesium. According to the 2020 American Heart Association guidelines, severe hypermagnesemia can lead to altered consciousness, bradycardia or ventricular arrhythmias, and cardiac arrest, and treatment may involve specific interventions such as calcium administration 1.
The clinical signs associated with severe hypermagnesemia include loss of tendon reflexes, sedation, severe muscular weakness, and respiratory depression, and can occur at magnesium levels of 4-5 mmol/L or higher 1. In cases of cardiac arrest associated with hypermagnesemia, administration of calcium (calcium chloride or calcium gluconate) may be considered 1. It is essential to seek immediate medical attention if a magnesium overdose is suspected, as prompt treatment can help prevent serious complications and improve outcomes.
Key points to consider in the management of magnesium overdose include:
- Stopping magnesium intake immediately
- Providing intravenous fluids to help eliminate excess magnesium
- Administering calcium gluconate to counteract magnesium's effects in severe cases
- Monitoring for signs of hypermagnesemia, such as loss of tendon reflexes, sedation, and respiratory depression
- Considering the patient's kidney function, as those with compromised kidney function are at higher risk of toxicity.
From the Research
Magnesium Overdose Symptoms and Causes
- Magnesium overdose can cause cardiac conduction delays, asystole, apnea, and coma 2
- Hypermagnesemia is a rare occurrence, particularly in the absence of renal failure, and is often iatrogenic 2
- Accidental overdose of magnesium can occur due to errors in drug administration, such as mistaken units of measurement 2
Risk Factors and Patient Profiles
- Patients with normal renal function can still experience fatal hypermagnesemia due to acute ingestion of magnesium-containing substances 3
- Over-the-counter magnesium-containing medications can be lethal if taken in large quantities or for prolonged periods 3
- Pediatric patients are also at risk of magnesium overdose, as seen in a case report of an 18-month-old girl who experienced an accidental overdose during a routine operation 4
Treatment and Management
- Patients with hypermagnesemia may require dialysis to control serum magnesium levels 5, 6
- Supportive therapy and close monitoring of serum magnesium levels are crucial in managing patients with magnesium overdose 3
- Education and awareness among healthcare personnel about the dosing regimens and adverse effects of magnesium are essential to prevent iatrogenic overdose 6