Ergocalciferol

Oral
Familial hypophosphataemia, Vitamin D-resistant rickets

Oral
Hypoparathyroidism

Oral
Vitamin D deficiency

Hypercalcaemia, metastatic calcification, evidence of vitamin D toxicity, hypervitaminosis D, abnormal sensitivity to toxic effects of vitamin D; malabsorption syndrome (unless dosed appropriately).

Patient with heart disease or arteriosclerosis, renal calculi, hyperphosphataemia. Obese patients (BMI >30 kg/m²). Treatment guidelines may vary among individual products (refer to product-specific recommendations). Renal impairment. Children. Pregnancy and lactation.

Significant: Hypercalcaemia, soft tissue calcification, hypercalciuria, vitamin D toxicity.
Gastrointestinal disorders: Nausea, abdominal pain, vomiting, constipation.
General disorders and administration site conditions: Weakness.
Investigations: Increased serum creatinine, weight loss.
Metabolism and nutrition disorders: Anorexia, thirst.
Nervous system disorders: Headache.
Renal and urinary disorders: Polyuria, nocturia.

PO: C

Monitor serum or urinary Ca and phosphorus concentrations, and BUN initially once or twice weekly then at regular intervals; renal function as clinically indicated. Perform bone X-ray every month until the condition is stabilised and corrected. Monitor for signs and symptoms of vitamin D toxicity.

Symptoms: Hypercalcaemia with anorexia, nausea, vomiting, constipation, diarrhoea, polyuria, nocturia, thirst, lassitude, headache, sweating, and vertigo. Management: Symptomatic and supportive treatment. In case of hypercalcaemia, discontinue treatment and initiate low Ca diet or generous fluid intake. May require hydration with IV saline solution in severe cases.

Mineral oil and colestyramine may interfere with the absorption of vitamin D. May cause hypercalcaemia with thiazide diuretics in hypoparathyroid patients. May reduce the efficacy with rifampicin and isoniazid. Metabolism may be increased by phenytoin. May increase the arrhythmogenic effects of cardiac glycosides.

Description:
Mechanism of Action: Ergocalciferol is a provitamin. Its active metabolite stimulates the Ca and phosphorous absorption by the small intestine, increases secretion of Ca from bone to blood, and promotes renal tubule phosphate reabsorption.
Synonym: calciferol, vitamin D₂.
Onset: 10-24 hours. Max effect: Approx 1 month (after daily doses).
Pharmacokinetics:
Absorption: Well absorbed from the small intestine.
Distribution: Crosses the placenta and enters breast milk. Distributed in fat, muscle, skin and bones.
Metabolism: Metabolised in the liver by vitamin D 25-hydroxylase via hydroxylation to form 25-hydroxyergocalciferol; further metabolised in the kidneys by vitamin D 1-hydroxylase to active 1,25-dihydroxyergocalciferol.
Excretion: Via faeces; urine (small amounts).

Source: National Center for Biotechnology Information. PubChem Compound Summary for CID 5280793, Ergocalciferol. https://pubchem.ncbi.nlm.nih.gov/compound/Ergocalciferol. Accessed Oct. 26, 2020.

Store between 15-30°C. Protect from light.

Vitamins A, D & E

A11CC01 - ergocalciferol ; Belongs to the class of vitamin D and analogues. Used as dietary supplements.

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Anon. Ergocalciferol. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 01/07/2020.

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Calciferol Capsules (British Dispensary Health Care). MIMS Thailand. http://www.mims.com/thailand. Accessed 15/09/2020.

Drisdol Capsule, Liquid Filled (Validus Pharmaceuticals LLC). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 05/07/2020.

Ergocalciferol Injection BP 300,000 U (RPH Pharmaceuticals AB). MHRA. https://products.mhra.gov.uk/. Accessed 05/07/2020.

Ergocalciferol Liquid (Virtus Pharmaceuticals). DailyMed. Source: U.S. National Library of Medicine. https://dailymed.nlm.nih.gov/dailymed/. Accessed 15/09/2020.

Ergocalciferol, Vitamin D2. Gold Standard Drug Database in ClinicalKey [online]. Elsevier Inc. https://www.clinicalkey.com/. Accessed 15/09/2020.

Joint Formulary Committee. Ergocalciferol. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 15/09/2020.