Vitamin D Deficiency
What Is It?
Low 25-hydroxyvitamin D levels (<20 ng/mL = deficiency, 20-29 = insufficiency). Associated with bone loss, muscle weakness, fatigue, immune dysfunction, and increased risk of many chronic diseases.
How Is It Diagnosed?
Serum 25-hydroxyvitamin D level. Check calcium, PTH, and phosphorus to assess for secondary hyperparathyroidism.
How Is It Treated?
Deficiency: vitamin D3 50,000 IU weekly for 8-12 weeks, then 1,500-2,000 IU daily maintenance. Calcium supplementation if dietary intake inadequate. Treat underlying malabsorption.
Tests and Imaging Typically Needed
25-hydroxyvitamin D, calcium, phosphorus, PTH, BMP, magnesium.
Approximate Self-Pay Costs
Office visit: $95-$150. Vitamin D level: $20-$35. Vitamin D3 supplements: $5-$15/month.