Common Questions
What are the available forms of vitamin D?
The four main forms of vitamin D are listed below. Note their equivalent pharmacologic doses and the duration of hypercalcemic, an effect that can be seen when using high doses to treat deficiency states.
| Type | Synonyms | Trade Name | Equivalent Doses/ Dosage | Duration of Hypercalcemic Action | Comment |
|---|---|---|---|---|---|
| Ergocalciferol | Vitamin D-2 | Calciferol | 1250 mcg (50,000 IU) | > 6 months | Form used in vitamins and to supplement foods. Derived from irradiated plant sterols. |
| Cholecalciferol | Vitamin D-3 | Cod liver oil 60 to 250 IU/capsule | Assumed same as above | > 6 months | Skin formation based on latitude, melanin, age. |
| Calcifediol | 25-hydroxy vitamin D(25 OH vitamin D) | Calderol | 50 mcg | 15 to 20 days | |
| Calcitriol | 1, 25-dihydroxy vitamin D(1, 25- OH2 vitamin D) | Rocaltrol | 1 mcg | 1 to 2 days | Used to treat the metabolic bone disease of renal failure. |