| abstract |
An osmotic dosage form which comprising: (a) a core comprising a biologically active ingredient; (b) a semi-permeable membrane covering said core; and (c) at least one passageway through the semi-permeable membrane, wherein the semi-permeable membrane comprises ethyl cellulose, an acrylic or methacrylic polymer and a water-soluble plasticizer with the proviso that the semi-permeable membrane comprises no or not more than 15 weight percent of a water-soluble material excluding any water-soluble plasticizer, based on the total dry weight of the semi-permeable membrane. |