Ergocalciferol is a form of vitamin D known as vitamin D2. It is the form of Vitamin D that is often incorporated in milk and nutritional supplements. This vitamin compound is readily available as a commercial alternative to organic vitamin D by-products found naturally in the environment. Vitamin D is an essential vitamin responsible for the absorption of calcium and phosphorus in the body leading to the development of stronger bones and teeth.
One use of ergocalciferol is for the treatment of hypoparathyroidism. Hypoparathyroidism is a condition where the parathyroid glands, located in the neck, insufficiently release parathyroid hormones. Parathyroid hormones are generally responsible for the balance of calcium in the blood. When calcium is insufficient, the body becomes prone to bone breakage or osteoporosis.
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Ergocalciferol is also given to patients with familial hypophosphatemia, a rare hereditary disease where vitamin D metabolism is altered and transport of phosphate is impaired. Ergocalciferol is also used to treat patients with refractory rickets, or rickets that does not respond to vitamin D treatment. Rickets is a common childhood disease caused by vitamin D deficiency. It is manifested by weakening of the bones, often resulting in bone deformities and fractures.
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Vitamin D supplements must be given with caution specifically to patients with hypercalcemia or elevated blood calcium levels, and those with malabsorption syndrome, which is the failure of the intestines to absorb nutrients. Ergocalciferol is also not recommended in individuals with hypervitaminosis D, or increased levels of vitamin D in the blood. Too much vitamin D in the blood is toxic to the body, and may lead to dehydration, kidney stones and kidney damage.
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Symptoms of increased levels of ergocalciferol in the body are constipation, irritability, decreased appetite and muscle weakness. Other notable side-effects include calcification of soft tissues, osteoporosis and gastric upsets. Prolonged intake of ergocalciferol may cause weight loss and anemia in some patients. It can also lead to mental retardation.
Hypervitaminosis D is treated with low-calcium diet and a withdrawal of the supplement. Hydration is also very important in order to dilute the calcium deposits in the blood and prevent calcification or hardening of the tissues. Some patients may need to be hospitalized in order to be given an intravenous saline infusion, which may help excrete calcium from the kidneys. An intravenous saline infusion is the administration of fluids and other substances through the veins of the patient.
There are several sources of vitamin D. One is through nutritional supplements in the form of ergocalciferol. Foods such as sardines, cod liver oil, and egg yolk are also rich in vitamin D. The most convenient source of vitamin D, however, is still sunlight.