Ergocalciferol (Vitamin D2)

Indications and Usage Section Ergocalciferol Capsules are indicated for use in the treatment of hypoparathyroidism, refractory rickets, also known as vitamin D resistant rickets, and familial hypophosphatemia.

Dosage and Administration Section DOSAGE AND ADMINISTRATION THE RANGE BETWEEN THERAPEUTIC AND TOXIC DOSES IS NARROW. Vitamin D Resistant Rickets: 12,000 to 500,000 IU units daily. Hypoparathyroidism: 50,000 to 200,000 IU units daily concomitantly with calcium lactate 4 g, six times per day. DOSAGE MUST BE INDIVIDUALIZED UNDER CLOSE MEDICAL SUPERVISION. Calcium intake should be adequate. Blood calcium and phosphorus determinations must be made every 2 weeks or more frequently if necessary. X-rays of the bones should be taken every month until condition is corrected and stabilized.

Contraindications Ergocalciferol Capsules are contraindicated in patients with hypercalcemia, malabsorption syndrome, abnormal sensitivity to the toxic effects of vitamin D, and hypervitaminosis D.

Warnings and Precautions Hypersensitivity to vitamin D may be one etiologic factor in infants with idiopathic hypercalcemia. In these cases vitamin D must be strictly restricted. Keep out of the reach of children. General Vitamin D administration from fortified foods, dietarysupplements, self-administered and prescription drug sources should be evaluated. Therapeutic dosage should be readjusted as soon as there is clinical improvement. Dosage levels must be individualized and great care exercised to prevent serious toxic effects. IN VITAMIN D RESISTANT RICKETS THE RANGE BETWEEN THERAPEUTIC AND TOXIC DOSES IS NARROW. When high therapeutic doses are used progress should be followed with frequent blood calcium determinations. In the treatment of hypoparathyroidism, intravenous calcium, parathyroid hormone, and/or dihydrotachysterol may be required. Maintenance of a normal serum phosphorus level by dietary phosphate restriction and/or administration of aluminum gels as intestinal phosphate binders in those patients with hyperphosphatemia as frequently seen in renal osteodystrophy is essential to prevent metastatic calcification. Adequate dietary calcium is necessary for clinical response to vitamin D therapy. Protect from light. Drug Interactions Mineral oil interferes with the absorption of fat-soluble vitamins,including vitamin D preparations. Administration of thiazide diuretics to hypoparathyroid patients who are concurrently being treated with Ergocalciferol Capsules may cause hypercalcemia. Carcinogenesis, Mutagenesis, Impairment of Fertility No long-term animal studies have been performed to evaluate the drug's potential in these areas. Pregnancy Pregnancy Category C Animal reproduction studies have shown fetal abnormalities in several species associated with hypervitaminosis D. These are similar to the supravalvular aortic stenosis syndrome described in infants by Black in England (1963). This syndrome was characterized by supravalvular aortic stenosis, elfin facies, and mental retardation. For the protection of the fetus, therefore, the use of vitamin D in excess of the recommended dietary allowance during normal pregnancy should be avoided unless, in the judgment of the physician, potential benefits in a specific, unique case outweigh the significant hazards involved. The safety in excess of 400 IU of vitamin D daily during pregnancy has not been established. Nursing Mothers Caution should be exercised when Ergocalciferol Capsules are administered to a nursing woman. In a mother given large doses of vitamin D, 25-hydroxycholecalciferol appeared in the milk and caused hypercalcemia in her child. Monitoring of the infant's serum calcium concentration is required in that case (Goldberg, 1972). Pediatric Use Pediatric doses must be individualized (see DOSAGE AND ADMINISTRATION). Geriatric Use Clinical studies of Ergocalciferol Capsules did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently from younger subjects. Other reported clinical experience has not identified differences in responses between the elderly and younger patients. A few published reports have suggested that the absorption of orally administered vitamin D may be attenuated in elderly compared to younger, individuals. In general, dose selection for an elderly patient should be cautious, usually starting at the low end of the dosing range, reflecting the greater frequency of decreased hepatic, renal, or cardiac function, and of concomitant disease or other drug therapy.

Adverse Reactions Hypervitaminosis D is characterized by effects on the following organ system: Renal: Impairment of renal function with polyuria, nocturia, polydipsia, hypercalciuria, reversible azotemia, hypertension, nephrocalcinosis, generalized vascular calcification, or irreversible renal insufficiency which may result in death. CNS: Mental retardation. Soft Tissues: Widespread calcification of the soft tissues, including the heart, blood vessels, renal tubules, and lungs. Skeletal: Bone demineralization (osteoporosis) in adults occurs concomitantly. Decline in the average rate of linear growth and increased mineralization of bones in infants and children (dwarfism) vague aches, stiffness, and weakness. Gastrointestinal: Nausea, anorexia, constipation. Metabolic: Mild acidosis, anemia, weight loss.