Vitamin D2 (Ergocalciferol)
Indications And Clinical Uses: Treatment of refractory rickets (vitamin D-resistant rickets), familial phosphatemia and hypoparathyroidism.
Contra-Indications: Hypercalcemia, malabsorption syndrome, abnormal sensitivity to the toxic effects of vitamin D, hypervitaminosis D, decreased renal function.
Precautions: Hypersensitivity to vitamin D may be one etiological factor in infants with idiopathic hypercalcemia. In these cases, vitamin D must be severely restricted.
Pregnancy: Safety in excess of 400 IU of vitamin D daily during pregnancy has not been established and animal reproduction studies in several species have shown fetal abnormalities associated with hypervitaminosis D. Avoid the use of vitamin D in excess of the recommended dietary allowance during pregnancy unless the potential benefits outweigh the possible adverse effects.
Vitamin D ingestion from fortified foods, milk with vitamin D added, dietary supplements and other sources should be evaluated.
Readjust therapeutic dosage as soon as there is clinical improvement. Individualize dosage levels and exercise great care to prevent serious toxic effects. In vitamin D-resistant rickets, the range between the therapeutic and toxic doses is narrow. When high therapeutic doses are used, follow progress with frequent serum and urinary calcium (Sulkowitch test), potassium and urea determinations.
In the treatment of hypoparathyroidism, calcium, parathyroid hormone and/or dihydrotachysterol may be required. Mineral oil interferes with the absorption of fat-soluble vitamins.
Symptoms And Treatment Of Overdose: Symptoms: Hypervitaminosis D is characterized by:
Hypercalcemia with anorexia, nausea, weakness, weight loss, vague aches and stiffness, constipation, diarrhea, convulsions, mental retardation, anemia, mild acidosis.
Impairment of renal function with polyuria, nocturia, polydipsia, hypercalcuria, reversible azotemia, hypertension, nephrocalcinosis, generalized vascular calcification, irreversible renal insufficiency, albuminuria, or urinary casts.
Widespread calcification of the soft tissues, including the heart, blood vessels, renal tubules, and lungs. 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).
Treatment: Immediate withdrawal of the vitamin, reduction of calcium intake and increased fluid intake. Hypercalcemic crisis requires more vigorous treatment. Intravenous saline may quickly and significantly increase urinary calcium excretion. Other reported therapeutic measures include dialysis or the administration of citrates, sulfates, phosphates, corticosteroids or EDTA.
Dosage And Administration: The recommended total daily intake of vitamin D from all sources is 400 IU. For the correction of vitamin D deficiency, 5 000 IU daily is recommended until a biochemical and radiographic response is apparent.
The range between therapeutic and toxic doses is narrow.
Vitamin D-resistant rickets: 12 000 to 500 000 IU daily.
Hypoparathyroidism: 50 000 to 200 000 IU daily plus 4 g of calcium lactate, administered 6 times per day.
Dosage must be individualized under close medical supervision. Calcium intake should be adequate. Blood calcium, phosphorus and urea determinations must be made every 2 weeks, or more frequently if necessary.
The bones should be x-rayed every month until the condition is corrected and stabilized.
Availability And Storage: Each clear yellow, soft gelatin capsule contains: vitamin D2 (ergocalciferol) 50 000 IU. Gluten-, lactose- and tartrazine-free. Bottles of 100. (Shown in Product Recognition Section)
OSTOFORTE® Frosst Vitamin D2 (Ergocalciferol) Vitamin
Posted by RxMed