Devit 50 000, D-Vit 5 000 and 10 000 are matrix tablets. Matrix tablets differ from other forms in that the active substance (cholecalciferol) is released slowly. This technology improves efficacy by increasing the amount of active ingredient that enters the bloodstream. And it has the maximum safety profile, as the concentration in the blood increases slowly, there is no sharp peak. Cholecalciferol is the inactive form of vitamin D. It requires two more conversions (in the liver and kidneys) to become the active form.