Causes	Management
Lack of adequate sunlight or chronic sunscreen	Ultraviolet lamp or increased sun exposure† use*
Total (central) parenteral nutrition	400 to 800 IU of vitamin D orally per day, or 20 to 25 IU of vitamin D per kg intravenously per day
Vitamin D–deficient diet	Usually 1,500 to 5,000 IU of vitamin D2 orally per day,  or 50,000 IU of vitamin D2 orally per week  or 10,000 to 50,000 IU of vitamin D2 intramuscularly per month
Fat malabsorption	25-hydroxyvitamin D, 20 to 30 mcg per day
Cirrhosis, nephrotic syndrome, renal failure, gastric or small bowel resection, rifampin, chronic corticosteroids, anticonvulsants	1,25-dihydroxyvitamin D, 0.15 to 0.5 mcg daily‡