title: Gastrointestinal therapeutic system delivering of a water insoluble drug: isosorbide dinitrate (ISDN).
abstract: An oral therapeutic system can only be effective for soluble drugs. If no suitable salt of a drug can be found, then an osmotic agent such as sodium chloride or mannitol has to be used in a modified two-chamber system, or the osmotic dispenser with collapsible supply container. A one-chamber gastrointestinal therapeutic system (GTS) is proposed which is capable of delivering insoluble drug at a relatively constant rate. The unit consists of a tablet containing the insoluble drug and the soluble carrier, surrounded by a rate-controlling membrane with a delivery orifice. If the unit is in contact with fluid, water will pass constantly through the membrane into the tablet, dissolve the carrier which will be pumping out the insoluble drug through the delivery orifice. The effect was studied of variable content and weight of the tablet, size of the delivery orifice and thickness of the membrane on the rate of insoluble drug release from the GTS.
mesh_terms: D005079:Excipients; D007548:Isosorbide Dinitrate / Q000008:administration & dosage*; D012995:Solubility; D013607:Tablets; D014783:Viscosity; D014867:Water
chemical_list: D005079:Excipients; D013607:Tablets; D014867:Water; D007548:Isosorbide Dinitrate