Low magnesium levels in the blood serum

Aetiology

• Alcohol
• Drugs - thiazide, PPIs
• GI illness with diarrhoea
• Pancreatitis
• Malabsorption

Clinical features

Symptoms

• Anorexia
• Nausea and vomiting
• Muscle weakness, lethargy
• Fits

Signs

• Cardiac arrhythmias
• Positive Chovestek sign and Trousseau sign indicate secondary hypocalcaemia

Investigations

• Bloods:
  • Serum magnesium low
  • Measure other electrolytes, particularly K+ and Ca2+

Management

• Magnesium supplementation, calcium supplementation if needed