Glipizide controlled release membrane pellet capsules

The present invention relates to a controlled release glipizide membrane pellet capsules, the pellets which release coating film using Eurdragit RL 30D as a film-forming material pellet core contains high expansion sodium carboxymethyl starch, and other pharmaceutically acceptable sustained-release pellets common excipients, preferably microcrystalline cellulose, lactose and sodium lauryl sulfate, wherein the pellet core accounted sodium carboxymethyl starch pellet core weight percentage of 5 ~ 20 %. Sustained release film coating comprising Eurdragit RL 30D, a plasticizer triethyl citrate and talc antisticking agent, preferably in a ratio of triethyl citrate Eurdragit RL 30D:: talc = 30:3:4, by coating preferably 17 to 36 weight%. Since the pellet cores containing sodium carboxymethyl starch having a high water-swelling property, water absorption after swelling significantly, resulting in release coating film is stretch, reducing the thickness, pore size becomes larger micropores permeable, the permeability becomes good compensation permeability decreased by aging of the membrane, so that the late release rate substantially constant, the residual small end, can always keep a stable release properties within the validity period.