Vitamin D3 (Cholecalciferol)
Generic Name: Cholecalciferol (Vitamin D3)
Uses & Medical Indications
Prevention and treatment of Vitamin D deficiency, rickets in children, osteomalacia in adults, and adjunctive therapy in postmenopausal and senile osteoporosis.
Vitamin D Deficiency, Osteoporosis, Rickets, Osteomalacia, Hypocalcemia
Work Mechanism & Pharmacology
Patient Overview of Work Mechanism
Vitamin D3 (Cholecalciferol) works at the cellular level to correct underlying biochemical imbalances, reduce clinical symptoms, and support overall health.
Clinical Mechanism of Action (MoA)
Vitamin D3 (Cholecalciferol) exerts targeted therapeutic activity by interacting with specific cellular receptors, enzymatic pathways, or biological signaling cascades to relieve symptoms and restore physiological balance.
Dosage & Administration Guidelines
Severe Deficiency (<20 ng/mL): 60,000 IU orally once weekly for 8 weeks, followed by maintenance 1,000 to 2,000 IU daily (or 60,000 IU once monthly). Routine maintenance: 1,000 to 2,000 IU daily.
Infants (0-12 months): 400 IU daily. Children >1 year: 600 to 1,000 IU daily. Clinical rickets treatment: 2,000 IU daily or 60,000 IU weekly for 6 weeks under pediatrician guidance.
1,000 to 2,000 IU daily to prevent falls and osteoporotic fractures.
4,000 IU daily for routine adult maintenance (upper safe limit).
Severe renal failure (eGFR <30 mL/min) impairs 1-alpha-hydroxylation in the kidney; active Calcitriol is preferred over Cholecalciferol.
No adjustment required.
Side Effects & Safety Warnings
Virtually none at physiological doses.
Hypervitaminosis D / Vitamin D Toxicity (hypercalcemia, renal calcinosis, metastatic calcification, cardiac arrhythmias - occurs with massive prolonged overdoses).
Hypercalcemia, hypervitaminosis D, malabsorption syndrome, calcium nephrolithiasis.
Do not take high-dose 60,000 IU capsules daily; 60,000 IU is designed strictly for weekly or monthly administration.
Interactions (Drugs, Food & Alcohol)
Thiazide diuretics (increased risk of hypercalcemia), Digoxin (hypercalcemia potentiates digoxin toxicity), Orlistat (reduces absorption).
Take with a meal containing dietary fat (milk, yogurt, eggs, olive oil) for optimal intestinal micelle absorption.
No direct interaction.
Pregnancy & Breastfeeding Safety
Safe and recommended; maternal vitamin D sufficiency is vital for fetal skeletal development (1,000-2,000 IU daily).
Excreted in small amounts; breastfed infants should receive 400 IU daily direct supplementation.
Patient Counseling & Practical Advice
Always take your Vitamin D capsule with your largest meal of the day containing healthy fats for best absorption. If prescribed 60,000 IU, take it only ONCE A WEEK, not every day.
Take when remembered that week. Do not double up weekly capsules.
Serum 25-hydroxyvitamin D [25(OH)D], serum calcium, albumin, phosphorus.
Frequently Asked Questions
Related Medicines in Vitamin
When to Seek Urgent Medical Attention
Severe confusion, vomiting, cardiac arrhythmias secondary to severe hypercalcemia.
Content for Vitamin D3 (Cholecalciferol) was synthesized from standardized public health monographs, official pharmacopoeias, and health authorities:
- Endocrine Society — Evaluation, Treatment, and Prevention of Vitamin D Deficiency
The information provided on this website is for educational purposes only and is not intended as a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of a qualified healthcare provider with any questions you may have regarding a medical condition.