What is the treatment for vitamin D deficiency?

Treatment of Vitamin D Deficiency

For vitamin D deficiency, the recommended treatment is oral ergocalciferol (vitamin D2) 50,000 IU once weekly for 8-12 weeks, followed by maintenance therapy of 800-2,000 IU daily of cholecalciferol (vitamin D3). 1, 2, 3

Initial Treatment Based on Deficiency Severity

• For vitamin D deficiency (<20 ng/mL), prescribe ergocalciferol 50,000 IU once weekly for 8-12 weeks 1, 2, 3
• For severe deficiency (<10 ng/mL), extend treatment to 12 weeks of weekly 50,000 IU doses, followed by monthly maintenance 1, 2
• For mild insufficiency (20-30 ng/mL), consider 4,000 IU daily for 12 weeks or 50,000 IU every other week for 12 weeks 2

Maintenance Therapy

• After achieving target levels (≥30 ng/mL), implement maintenance therapy with cholecalciferol 800-2,000 IU daily 1, 2, 3
• For convenience, a monthly dose of 50,000 IU can achieve the equivalent of approximately 1,600 IU daily 1
• Cholecalciferol (vitamin D3) is preferred over ergocalciferol (vitamin D2) for maintenance therapy due to higher bioefficacy 2, 4

Special Populations

• For adults over 60 years, a minimum of 800 IU daily is recommended, while for younger adults 400 IU daily is typically sufficient 5, 1
• For patients with chronic kidney disease (CKD) and GFR of 20-60 mL/min/1.73m², nutritional vitamin D deficiency can be treated with ergocalciferol or cholecalciferol 5, 1
• For patients with malabsorption or those not responding to oral supplementation, consider parenteral vitamin D (typically as IM injection of 50,000 IU) 1

Monitoring and Follow-up

• Recheck vitamin D levels after 3-6 months of supplementation to ensure adequate response 1, 2, 3
• Target serum 25(OH)D level should be at least 30 ng/mL for optimal bone health and anti-fracture efficacy 1, 2
• Assess for symptoms of vitamin D toxicity including hypercalcemia, hypercalciuria, and renal issues 1, 2

Important Considerations

• Ensure adequate calcium intake (1,000-1,500 mg daily) alongside vitamin D supplementation, as this is necessary for response to vitamin D therapy 1, 2, 6
• Avoid single very large doses (>300,000 IU) as they may be inefficient or potentially harmful 1, 7
• Daily doses up to 4,000 IU are generally considered safe for adults 2
• Vitamin D toxicity is rare but can occur with prolonged high doses (typically >10,000 IU daily) 1, 2

Common Pitfalls to Avoid

• Not ensuring adequate calcium intake alongside vitamin D supplementation 2, 6
• Using active vitamin D analogs (calcitriol, alfacalcidol) to treat vitamin D deficiency instead of cholecalciferol or ergocalciferol 2
• Failing to recognize that individual response to vitamin D supplementation varies due to genetic factors, body composition, and environmental influences 1, 8
• Not accounting for the higher dosage requirements in obesity, as vitamin D is sequestered in adipose tissue 1

Practical Dosing Algorithm

1. Measure baseline 25(OH)D level 9
2. For levels <20 ng/mL: Prescribe ergocalciferol 50,000 IU weekly for 8-12 weeks 1, 2, 3
3. For levels 20-30 ng/mL: Prescribe 4,000 IU daily for 12 weeks or 50,000 IU every other week for 12 weeks 2
4. Recheck levels after treatment course 1, 3
5. Implement maintenance therapy with cholecalciferol 800-2,000 IU daily 1, 2, 3
6. Ensure adequate calcium intake of 1,000-1,500 mg daily 1, 2, 6