Product Description

Introduction

Colecalciferol (Vitamin D3) is used for the prevention and treatment of vitamin D deficiency and related bone disorders. It is indicated in conditions such as osteoporosis, hypoparathyroidism, rickets, osteomalacia, pseudohypoparathyroidism, and familial hypophosphatemia.

Administration

May be taken with or without food.

Adult Dose

For nutritional deficiency: 200–400 IU (5–10 mcg or 1–2 ml) daily, orally or by intramuscular injection.

For osteoporosis prevention and treatment (>50 years): 800–1000 IU (20–25 mcg) once daily with calcium supplements; may also be given by intramuscular injection.

For hypoparathyroidism: 50,000–200,000 IU (0.625–5 mg) once daily with calcium supplements; may also be given by intramuscular injection.

Child Dose

For nutritional supplementation:

0–12 months: 400 IU (10 mcg) once daily

1–18 years: 600 IU (15 mcg) once daily

For vitamin D–resistant rickets: 12,000–500,000 IU (0.3–12.5 mg) once daily.

For familial hypophosphatemia: 40,000–80,000 IU (1–2 mg) once daily with phosphate supplements; dose may be reduced after growth completion.

Contraindication

Colecalciferol is contraindicated in patients with hypercalcemia, vitamin D toxicity, or known hypersensitivity to vitamin D or any of its components.

Mode of Action

Vitamin D3 is a fat-soluble sterol that regulates calcium and phosphate balance and supports bone mineralization. It improves calcium absorption from the gastrointestinal tract and promotes bone formation.

Precaution

Use with caution in patients with high calcium or phosphate levels, heart disease, or kidney disease. Adequate calcium and magnesium intake is required during therapy. Low calcium levels trigger parathyroid hormone release, which affects calcium regulation in bones. Vitamin D passes into breast milk and should be used carefully during lactation.

Side Effect

Vitamin D is generally well tolerated. Excess intake may cause hypercalcemia or calcium toxicity. Symptoms may include loss of appetite, headache, dry mouth, nausea, vomiting, abdominal pain, and constipation.

Interaction

Risk of hypercalcemia increases with thiazide diuretics, calcium, or phosphate supplements. Antiepileptic drugs (carbamazepine, phenytoin, phenobarbitone, primidone) may increase vitamin D requirement. Rifampicin and isoniazid may reduce its effect. Corticosteroids may reduce its action. Absorption may be reduced with cholestyramine, colestipol, mineral oil, orlistat. Caution with digoxin and ketoconazole.