

Indications and Usage for Drisdolĭrisdol is indicated for use in the treatment of hypoparathyroidism, refractory rickets, also known as vitamin D resistant rickets, and familial hypophosphatemia. Parathyroid hormone is responsible for the regulation of this metabolism in the kidneys. There is a time lag of 10 to 24 hours between the administration of vitamin D and the initiation of its action in the body due to the necessity of synthesis of the active metabolites in the liver and kidneys. Vitamin D metabolites also mobilize calcium and phosphate from bone and probably increase the reabsorption of calcium and perhaps also of phosphate by the renal tubules. Vitamin D metabolites promote the active absorption of calcium and phosphorus by the small intestine, thus elevating serum calcium and phosphate levels sufficiently to permit bone mineralization. The first hydroxylation of ergocalciferol takes place in the liver (to 25-hydroxyvitamin D) and the second in the kidneys (to 1, 25-dihydroxyvitamin D). The in vivo synthesis of the major biologically active metabolites of vitamin D occurs in two steps. Inactive Ingredients: FD&C Blue #1, FD&C Yellow #5, Gelatin, Glycerin, Soybean Oil. One USP unit of vitamin D 2 is equivalent to one International Unit (IU), and 1 mcg of vitamin D 2 is equal to 40 IU.Įach capsule contains 1.25 mg (50,000 International Units vitamin D) of ergocalciferol, USP, in an edible vegetable oil.Įrgocalciferol, also called vitamin D 2, is 9, 10-secoergosta-5,7,10 (19), 22-tetraen-3-ol, (3ß,5Z,7E, 22 E)- (C 2 8H 4 4O) with a molecular weight of 396.65, and has the following structural formula: There are more than 10 substances belonging to a group of steroid compounds, classified as having vitamin D or antirachitic activity. Ergosterol or provitamin D 2 is found in plants and yeast and has no antirachitic activity. Drisdol brand of ergocalciferol capsules, USP, is a synthetic calcium regulator for oral administration.Įrgocalciferol is a white, colorless crystal, insoluble in water, soluble in organic solvents, and slightly soluble in vegetable oils.
