What are the symptoms of hypercalcemia?

Symptoms of Hypercalcemia

Hypercalcemia presents with a spectrum of symptoms affecting multiple body systems, ranging from mild constitutional symptoms to severe life-threatening manifestations depending on calcium levels and rate of onset. 1

Symptom Categories by Body System

Neurological Symptoms

• Altered mental status
• Irritability
• Confusion
• Somnolence
• Coma (in severe cases)
• Fatigue and weakness 2, 1

Gastrointestinal Symptoms

• Nausea
• Vomiting
• Constipation
• Anorexia 2, 3

Renal Symptoms

• Polyuria (excessive urination)
• Polydipsia (excessive thirst)
• Renal injury
• Development of kidney stones 2, 1

Cardiovascular Symptoms

• Cardiac arrhythmias (especially with rapid changes in calcium levels)
• QT interval prolongation on ECG
• Rarely, cardiomyopathy 2, 1

Musculoskeletal Symptoms

• Muscle weakness
• Abnormal involuntary movements
• Bone pain (in chronic cases) 2, 4

Severity Correlation

The severity of symptoms typically correlates with both the absolute calcium level and the rate of rise:

• Mild hypercalcemia (total calcium <12 mg/dL or <3 mmol/L):

  • Often asymptomatic
  • Constitutional symptoms like fatigue and constipation in approximately 20% of patients 3

• Moderate hypercalcemia (total calcium 12-14 mg/dL or 3-3.5 mmol/L):

  • More pronounced gastrointestinal and neurological symptoms
  • Increased risk of dehydration 4

• Severe hypercalcemia/Hypercalcemic crisis (total calcium ≥14 mg/dL or ≥3.5 mmol/L):

  • Marked neurological impairment
  • Severe dehydration
  • Risk of coma
  • Life-threatening complications 1, 4

Important Clinical Considerations

• Symptoms may be exacerbated during periods of biological stress (surgery, fracture, injury, childbirth, infection) 2
• Hypercalcemia may be worsened by alcohol or soda drinks, especially colas 2
• Rapid onset hypercalcemia typically produces more severe symptoms than gradually developing hypercalcemia 3
• Symptoms may be confused with other conditions, particularly in elderly patients or those with multiple comorbidities 1

Common Pitfalls in Recognizing Hypercalcemia

• Attributing nonspecific symptoms (fatigue, weakness, confusion) to other causes, especially in elderly patients
• Failing to consider hypercalcemia in patients with unexplained neuropsychiatric symptoms
• Not recognizing the relationship between hypercalcemia and movement disorders or seizures 2, 1
• Overlooking hypercalcemia as a cause of cardiac arrhythmias or QT interval changes 1

Early recognition of these symptoms is crucial for prompt diagnosis and treatment, as severe untreated hypercalcemia can lead to significant morbidity and mortality, particularly in cases of hypercalcemic crisis 4.