Hypocalcemia

Hypocalcemia occurs when serum calcium levels fall below the typical range of 8.5 to 10.2 mg/dL. Because calcium is a vital electrolyte, its deficiency disrupts critical physiological processes, including bone mineralization, blood clotting, and enzymatic activity. The condition often arises secondary to underlying health issues such as hormonal imbalances—notably parathyroid deficiency, vitamin D insufficiency, hypomagnesemia, or chronic kidney disease.

Mild hypocalcemia may remain asymptomatic, especially if the decline is gradual. However, as levels drop further, the increased excitability of nerves and muscles can lead to the mnemonic "CATs go numb"—representing convulsions, arrhythmias, tetany, and paresthesia. Symptoms often manifest as tingling in the extremities and around the mouth, involuntary muscle spasms or cramps, and in severe cases, life-threatening seizures or cardiac rhythm disturbances.

Diagnosis and Management

Diagnosis is established through blood tests measuring serum calcium, often accompanied by evaluations of PTH, vitamin D, phosphate, and magnesium levels to identify the root cause. Treatment strategies focus on correcting the primary underlying condition while restoring systemic calcium balance. Common interventions include oral calcium and vitamin D supplementation for chronic management, while acute or severe manifestations may require hospitalization and the administration of intravenous calcium to rapidly stabilize neurological and cardiac function.