From the Research
For a patient with a vitamin D level of 19 nmol/L, I recommend prescribing 50,000 IU of vitamin D2 (ergocalciferol) or vitamin D3 (cholecalciferol) once weekly for 8 weeks, followed by maintenance therapy of 1,000-2,000 IU daily. This recommendation is based on the study by 1, which suggests that treatment of vitamin D deficiency may include oral ergocalciferol (vitamin D2) at 50,000 IU per week for eight weeks, and maintenance dosages of cholecalciferol (vitamin D3) at 800 to 1,000 IU per day from dietary and supplemental sources.
Rationale for Recommendation
The patient's vitamin D level of 19 nmol/L indicates severe deficiency, which can lead to bone demineralization, muscle weakness, and increased fracture risk. The weekly high-dose regimen helps rapidly replenish vitamin D stores, while the maintenance dose prevents recurrence of deficiency.
Important Considerations
- Patients should take vitamin D supplements with food containing some fat to enhance absorption.
- Adequate dietary calcium intake or supplementation (1000-1200 mg daily) should be encouraged to optimize bone health during vitamin D repletion.
- After completing the 8-week loading dose regimen, the patient's vitamin D levels should be rechecked to ensure improvement. If levels remain low, another course of weekly high-dose therapy may be needed.
Supporting Evidence
The study by 2 also supports the use of high-dose vitamin D therapy, demonstrating that rapid substitution with 50,000 IU oral cholecalciferol daily for 7 days can increase vitamin D plasma levels rapidly and safely. However, the study by 1 provides more specific guidance on the treatment of vitamin D deficiency, making it the primary basis for this recommendation.