Rocaltrol, a brand-name version of Calcitriol, is available by prescription in capsule form in different strengths. Rocaltrol is the active form of vitamin D, normally made in the kidney. It is also known as 1,25-dihydroxycholecalciferol. It is a hormone which binds to and activates the vitamin D receptor in the nucleus of the cell, which then increases the expression of many genes. You can save on brand Rocaltrol by shopping online at our Online Pharmacy.