Cadla is chemically Alfacalcidol (1 a-hydroxyvitamin D3) is rapidly converted in the liver to 1,25-dihydroxyvitamin D3, a metabolite of vitamin D3 that regulates calcium and phosphate homeostasis. Impaired endogenous production of 1,25-dihydroxyvitamin D3 by the kidney contributes to the disturbances in mineral metabolism found in disorders like renal bone disease, hypo-parathyroidism and vitamin D-dependant rickets. Higher doses of vitamin D are required in these disorders for their correction, but smaller doses of Cadla are equally effective. The main advantage of Cadla over vitamin D is that it provides much more accurate dose titration and decreased risk of hypercalcaemia owing to the rapid onset and reversal of action.
Serum levels of 1,25-dihydroxyvitamin2 D3peak approximately 12 hours after a single dose of Cadla and remain at measurable levels for at least 48 hours. The effect of 1 N9 of Cadla on calcium absorption has been observed within 6 hours and was maximal at 24 hours. The biological half-life is approximately 35 hours.