Mechanism of action of calcitriolcalcitriol is a 1, 25-dihydroxycholecalciferol or a vitamin d analogue. it increases the absorption of calcium from intestine by forming a calcium binding protein. it reverses the signs of rickets and osteomalacia.pharmacokinets of calcitriolabsorption: it is readily absorbed after oral administration. distribution: it is widely distributed in protein bound form. metabolism: it undergoes metabolism in the liver and kidney. excretion: it is excreted mainly in the faeces.indications for calcitriol1.management of hypocalcaemia 2.management of hypoparathyroidism and pseudohypoparathyroidism