Ambroxol hydrochloride controlled release membrane pellet capsules

The present invention relates to one kind of amino ambroxol hydrochloride controlled release membrane pellet capsules, the pellets which release coating film using Kollicoat SR 30D as a film-forming material pellet core contains high expansion low substituted hydroxypropylcellulose, and pharmaceutically acceptable sustained-release pellets commonly used excipients such as, preferably microcrystalline cellulose and lactose, wherein the pellet core low-substituted hydroxypropyl cellulose pellet core weight percentage of 10 to 40%. Sustained release film coating comprising Kollicoat SR30D, plasticizer triethyl citrate and talc antisticking agent, preferably in a ratio of triethyl citrate Kollicoat SR 30D:: talc = 30:1.5:4, coating weight preferably from 20 to 36%. Because it contains water having a high expansion low-substituted hydroxypropylcellulose of the pellet core, significantly swell after absorbing water, resulting in release coating film is stretch, reducing the thickness, pore size becomes larger micropores permeable, the permeability variation well, the compensation film permeability decreased by aging, such that substantially constant release rate in the latter part, the end of the remaining small, can always keep a stable release properties within the validity period.