Drisdol - General Information
Drisdol (Vitamin D2) is a derivative of ergosterol formed by ultraviolet rays breaking of the C9-C10 bond. It differs from cholecalciferol in having a double bond between C22 and C23 and a methyl group at C24. [PubChem]
Pharmacology of Drisdol
Used in the treatment of hypcalcemia and in dialysis-dependent renal failure. Ergoalcifediol (Vitamin D2) is a fat soluble steroid hormone precursor of vitamin D that contributes to the maintenance of normal levels of calcium and phosphorus in the bloodstream.
Drisdol for patients
Patient information for vitamin D analogues (Vitamin D2, Vitamin D3, Calcitriol, and Calcidiol):
The patient and his or her parents or s.o.s. should be informed about compliance with dosage instructions, adherence to instructions about diet and calcium supplementation and avoidance of the use of unapproved nonprescription drugs. Patients should also be carefully informed about the symptoms of hypercalcemia.
The effectiveness of vitamin D therapy is predicated on the assumption that each patient is receiving an adequate daily intake of calcium. Patients are advised to have a dietary intake of calcium at a minimum of 600 mg daily. The U.S. RDA for calcium in adults is 800 mg to 1200 mg.
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 may cause hypercalcemia.
Ergocalciferol is contraindicated in patients with hypercalcemia, malabsorption syndrome, abnormal sensitivity to the toxic effects of vitamin D, and hypervitaminosis D.
Additional information about Drisdol
Drisdol Indication: For use in the treatment of hypoparathyroidism, refractory rickets, also known as vitamin D resistant rickets, and familial hypophosphatemia.
Mechanism Of Action: Vitamin D2 is the form of vitamin D most commonly added to foods and nutritional supplements. Vitamin D2 must be transformed (hydroxylated) into one of two active forms via the liver or kidney. Once transformed, it binds to the vitamin D receptor that then leads to a variety of regulatory roles. Vitamin D plays an important role in maintaining calcium balance and in the regulation of parathyroid hormone (PTH). It promotes renal reabsorption of calcium, increases intestinal absorption of calcium and phosphorus, and increases calcium and phosphorus mobilization from bone to plasma. Vitamin D2 and its analogs appear to promote intestinal absorption of calcium through binding to a specific receptor in the mucosal cytoplasm of the intestine. Subsequently, calcium is absorbed through formation of a calcium-binding protein.
Drug Interactions: Not Available
Food Interactions: Not Available
Generic Name: Ergocalciferol
Synonyms: Vitamin D2; Synthetic Vitamin D
Drug Category: Antihypocalcemic Agents; Antihypoparathyroid Agents; Essential Vitamin; Vitamins (Vitamin D)
Drug Type: Small Molecule; Nutraceutical; Approved
Absorption: Readily absorbed from small intestine (proximal or distal), requires presence of bile salts.
Toxicity (Overdose): LD50 = 23.7 mg/kg (Orally in mice); LD50 = 10 mg/kg (Orally in rats ); Nausea, vomiting and diarrhea, weight loss, irritability, weakness, fatigue, lassitude, and headache.
Protein Binding: >99.8%
Biotransformation: Within the liver, ergocalciferol is hydroxylated to ercalcidiol (25-hydroxyergocalciferol) by the enzyme 25-hydroxylase. Within the kidney, ercalcidiol serves as a substrate for 1-alpha-hydroxylase, yielding ercalcitriol (1,25-dihydroxyergocalciferol), the biologically active form of vitamin D2.
Half Life: 19 to 48 hours (however, stored in fat deposits in body for prolonged periods).
Dosage Forms of Drisdol: Capsule Oral
Chemical IUPAC Name: (1S,3Z)-3-[(2E)-2-[(1R,3aS,7aR)-1-[(E,2R,5R)-5,6-dimethylhept-3-en-2-yl]-7a-methyl-2,3,3a,5,6,7-hexahydro-1H-inden-4-ylidene]ethylidene]-4-methylidenecyclohexan-1-ol
Chemical Formula: C28H44O
Ergocalciferol on Wikipedia: https://en.wikipedia.org/wiki/Ergocalciferol
Organisms Affected: Humans and other mammals