ABSTRACT
<p><b>OBJECTIVE</b>To investigate the release model of insoluble drug carbamazepine (CBM) based on HPMC matrix tablets.</p><p><b>METHODS</b>CBM release profile from matrices and HPMC erosion rate were determined.</p><p><b>RESULT</b>The mathematical model by matrix erosion rate and drug release from HPMC K15M were established for the fractional HPMC and CBM released as M(P(t))/M(P(infinity))=-[0.8095ln((t))+1.2775]Meq((-0.0622t-0.305)) and M(d(t))/M(d(infinity))=-[0.1891t-0.1294]Meq(-0.9326). In comparison with the data of HPMC K4M matrix erosion and CBM release from HPMC K4M matrices, theoretical value agreed well with experimental data.</p><p><b>CONCLUSION</b>The two mathematical models can be satisfactorily applied to insoluble drug release, which is governed by matrix erosion.</p>