The spectrum of hypocalcemia ranges from an asymptomatic biochemical abnormality to a life-threatening medical emergency with manifestations such as paresthesias, carpopedal spasm, tetany, and seizures. Its management will depend on factors such as rapidity of onset, the extent of the fall in serum calcium, the presence of signs and symptoms, and its likely cause. The aims of acute management are to safely raise the serum calcium to a level at which symptoms dissipate and to prevent serious cardiac disturbance. Symptomatic patients and those with an acute decrease in serum calcium to less than 1.9 mmol/L (7.6 mg/dL) usually require the intravenous administration of calcium salts. Asymptomatic patients with milder degrees of hypocalcemia can often be managed with oral calcium preparations, with or without the addition of vitamin D (or one of its analogues).