How should vitamin D deficiency be treated and what are target levels?

• A. Repletion with high-dose vitamin D (e.g., 50,000 IU weekly for 6–8 weeks or equivalent) followed by maintenance; target 25‑OH vitamin D > 30 ng/mL.
• B. Treatment with calcium only; vitamin D is not required.
• C. Only sunlight exposure.
• D. Maintenance with 400 IU daily forever.

Answer: (A)

Treating vitamin D deficiency involves first repleting stores quickly and then maintaining adequate levels to support calcium absorption and bone health. A repletion plan uses a high-dose vitamin D approach to raise the 25‑OH vitamin D level into a normal range, followed by a maintenance dose to keep it there. A commonly used repletion strategy is 50,000 IU of vitamin D weekly for about 6–8 weeks, then switching to a ongoing maintenance dose. The goal is to achieve a 25‑OH vitamin D level above 30 ng/mL, with higher targets sometimes used depending on guidelines and individual risk factors. This approach is preferred because relying on calcium alone or just sunlight exposure doesn’t reliably correct deficiency or sustain adequate levels, and a maintenance dose of 400 IU daily is generally insufficient to correct and maintain normal vitamin D status.