Ergocalciferol
Generic name: ergocalciferol · Brand names: Ergocalciferol
Provitamin D2 Compound [epc]Information sourced from FDA Structured Product Labeling, updated May 20, 2026.
What is it used for?
Ergocalciferol is indicated for use in the treatment of hypoparathyroidism, refractory rickets, also known as vitamin D resistant rickets, and familial hypophosphatemia.
How to take it
DOSAGE AND ADMINISTRATION THE RANGE BETWEEN THERAPEUTIC AND TOXIC DOSES IS NARROW. Vitamin D Resistant Rickets: 12,000 to 500,000 USP units daily. Hypoparathyroidism: 50,000 to 200,000 USP 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 phosphorous 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.
Warnings
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.
Who should not take it
Ergocalciferol is contraindicated in patients with hypercalcemia, malabsorption syndrome, abnormal sensitivity to the toxic effects of vitamin D, and hypervitaminosis D.
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. 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 USP units of vitamin D daily during pregnancy has not been established.
Breastfeeding
Nursing Mothers Caution should be exercised when ergocalciferol 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).
Side effects
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. To report SUSPECTED ADVERSE REACTIONS, contact Bionpharma Inc. at 1-888-235-2466 or FDA at 1-800-FDA-1088 or www.fda.gov/ medwatch.
All information on this site is provided “as-is” for informational purposes only and is not a substitute for medical advice or treatment. You should consult with a medical professional if you have any questions about your health. Source: FDA Structured Product Labeling.