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.
Vitamin D administration from fortified foods, dietary supplements, 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.
This product contains FD&C Yellow No. 5 (tartrazine) which may cause allergic-type reactions (including bronchial asthma) in certain susceptible individuals. Although the overall incidence of FD&C Yellow No. 5 (tartrazine) sensitivity in the general population is low, it is frequently seen in patients who also have aspirin hypersensitivity.
Protect from light.
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 DRISDOL 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 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.
Caution should be exercised when DRISDOL is 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 doses must be individualized (see DOSAGE AND ADMINISTRATION).
Clinical studies of DRISDOL 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.