Generalities:

Hypocalcemia: calcium deficiency. The parotid glands control the metabolism of calcium, the serum levels of the ion that must be less than 2.1 mmol / L or 8.5 mg / dL. It also controls its storage in the bones. Hypocalcemia causes an imbalance in the cell membranes between the calcium and sodium ions, affecting the muscles and the nervous system. The heart is one of the organs that is most at risk with this condition

Also check the pair of  Parotids.