a vitamin - treats Osteogenesis imperfecta, Proximal myopathy, Fall prevention, Colorectal cancer, Skin pigmentation disorders, Vitamin D deficiency, Hepatic osteodystrophy, Muscle weakness/pain, Immunomodulation, Muscle strength, Fanconi syndrome-related hypophosphatemia, Mortality reduction, Psoriasis, Hypocalcemia due to hypoparathyroidism, Cancer prevention, Breast cancer prevention, Senile warts, Tooth retention, Corticosteroid-induced osteoporosis, Anticonvulsant-induced osteomalacia, Hypertriglyceridemia, Multiple sclerosis, High blood pressure, Osteoporosis, Diabetes, Seasonal affective disorder, Myelodysplastic syndrome, Prostate cancer, Familial hypophosphatemia, Rickets, Renal osteodystrophy, Weight gain, Hyperparathyroidism due to low vitamin D levels, and Osteomalacia
Interactions with Drugs
Decreased vitamin D effects may occur with the use of certain anti- seizure drugs, as they may induce hepatic microsomal enzymes and accelerate the conversion of vitamin D to inactive metabolites.
Based on mechanism of action, use of vitamin D and calcium together may alter inflammatory response.
Intestinal absorption of vitamin D may be impaired with the use of these agents. Patients on cholestyramine or colestipol should be advised to allow as much time as possible between the ingestion of these drugs and vitamin D.
Use of corticosteroids can cause osteoporosis and calcium depletion with long- term administration. This calcium depletion creates a greater need for both supplemental calcium and vitamin D (which is necessary for calcium absorption).
Intestinal absorption of vitamin D may be impaired with the use of mineral oil.
Rifampin increases vitamin D metabolism and reduces vitamin D blood levels. The need for vitamin D supplementation with rifampin has not been thoroughly studied, although additional supplementation may be necessary.
Stimulant laxatives can reduce dietary vitamin D absorption. Stimulant laxatives should be limited to short- term use if possible.
Concurrent administration of thiazide diuretics and vitamin D to hypoparathyroid patients may cause hypercalcemia, which may be transient or may require discontinuation of vitamin D. Examples of thiazide diuretics include chlorothiazide (Diuril®), chlorthalidone (Hygroton®, Thalitone®), hydrochlorothiazide (HCTZ®, Esidrix®, HydroDIURIL®, Ortec®, Microzide®), indapamide (Lozol®), and metolazone (Zaroxolyn®).
Interactions with Herbs and Dietary Supplements
Based on mechanism of action, the use of vitamin D and calcium together may alter inflammatory response.
Vitamin D should be used with caution in patients taking herbs with similar properties on the heart as digoxin, because hypercalcemia (which may result with excess vitamin D use) may precipitate abnormal heart rhythms.
Vitamin D is necessary for calcium absorption. Vitamin D is often included in calcium supplement products.