hypermagnesemia

Etiology

• uncommon in patients without renal failure or small bowel hypomorility
• excessive magnesium therapy for pre-eclampsia

Clinical manifestations

• central nervous system
  • somnolence, lethargy
  • depression of deep tendon reflexes (DTR)
  • paralysis of peripheral & respiratory muscles
  • coma
• cardiac
  • hypotension
  • heart block
  • arrhythmias
  • cardiac arrest
• GI
  • nausea
  • abdominal tenderness
  • bloating

Laboratory

• serum magnesium:
  • symptoms emerge when > 5.0-7.2 mg/dL (> 4.8 mg/dL)
    • normal: 1.5-2.4 mg/dL

Management

• discontinue magnesium-containing medications
• intravenous calcium gluconate antagonizes effects of hypermagnesemia
  • indicated for serum magnesium > 6.0 mg/dL
• volume expansion with normal saline + furosemide to enhance urine Mg+2 excretion
  • for symptomatic patients with chronic kidney disease
• dialysis in Mg+2-intoxicated patients with renal insufficiency

More general terms

• electrolyte disorder
• sign/symptom
• disorder of magnesium metabolism

Additional terms

• calcium gluconate
• magnesium (Mg+2) in serum