| 摘要 |
<p>This invention relates to sustained-release, solid-dosage forms having non-uniform distribution of active ingredient which provides for zero-order release of the active ingredient. The non-uniform distribution is accomplished by providing for a multitude of enveloping, concentric layers over a central core. Each of the various layers having constant concentration of a hydrophilic gel and each layer and the core having an amount of medicament defined by the expression DL = DT x R/R@. wherein DL is the amount of medicament in the core or in any given sustained-release layer, DT is the total amount of medicament in the sustained-release portion of the tablet, RD is the differential radius for the core or the enveloping layer for which the amount of required medicament is to be determined and RT is the radius of the sustained-release portion of the tablet.</p> |
