Elevated blood calcium levels, or hypercalcemia, are never normal. The usual cause of high calcium in the blood is a condition known as hyperparathyroidism, or parathyroid disease. A benign tumor in the parathyroid glands causes high levels of calcium in 98 percent of cases, and the usual treatment is thyroid surgery.
The parathyroid glands regulate the amount of calcium in the blood. When they become overactive, then elevated blood calcium levels are the result. There are very few cases where the cause of the condition is due to cancer, medications and overuse of calcium and vitamin D supplements.
In mild cases, there are few symptoms, but in the more severe cases, symptoms include nausea, constipation, thirst, muscle and joint aches, loss of appetite and muscle weakness. If left untreated, severe hypercalcemia can result in osteoporosis, kidney stones, kidney failure, nervous system dysfunction and arrhythmia, or abnormal heart rhythm. A blood test will indicate if there are elevated levels of calcium in the blood.
In cases of mild hypercalcemia, the doctor may choose to adopt a wait-and-see approach, monitoring the condition to ensure bone strength and the healthy function of the kidneys. Surgery to remove the parathyroid gland or glands cures the condition in the majority of cases. This may be carried out using a radioisotope scan to identify the gland responsible before the actual surgery, which cuts down on the invasiveness of the procedure. If surgery is not an option, elevated blood calcium levels can be controlled by the use of medication such as cinacalcet. This lowers the levels by reducing the production of the parathyroid hormone.
In severe cases, treatment requires hospitalization where intravenous fluids are introduced in order to rehydrate before loop diuretic medications flush out the excess calcium. Drugs such as pamidronate and zolendronate protect the bones from breaking down, and calcitonin, which is a hormone produced by the thyroid gland, slows down bone loss. Hemodialysis is usually a last resort if there has been damage to the kidneys, and the condition does not respond to any of the other treatments.
Elevated blood calcium levels can lead to bone and kidney damage. To reduce the possibility of this happening, some lifestyle changes can be introduced. It is very important to drink plenty of water, as this prevents kidney stones from developing. Once calcium levels have been restored to normal, exercise helps maintain bone density, as does quitting smoking.