calcitriol

Calcitriol (INN) (IPA: ) or 1,25-dihydroxycholecalciferol (abbreviated 1,25-(OH)2D3) is the active form of vitamin D found in the body (vitamin D3). Calcitriol is marketed under various trade names including Rocaltrol (Roche), Calcijex (Abbott) and Decostriol (Mibe, Jesalis).
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Calcitriol /cal·ci·tri·ol/ 1. see dihydroxycholecalciferol. 2. a preparation of this compound, used in the treatment of hypocalcemia, [more]Calcitriol - Community and Resources

[kal-sih-TREE-ol]
The active form of vitamin D. Calcitriol is formed in the kidneys or made in the laboratory. It is used as a drug to increase calcium levels in the body in order to treat skeletal and tissue-related calcium deficiencies caused by kidney or thyroid disorders.