Osmotically enhanced drug release from hydrophobic elastomeric matrices

Fractional drug release (a) 1.0 0.8 0.6 0.4 0.2 0.0 (b) t1/2 (days1/2) The analysis of drug release and concurrent water uptake kinetic data presented above provides useful information on the mechanism of osmotically enhanced drug release from hydrophobic polymeric matrices. The observed large increase in drug release is attributable to excess swelling and accompanying structural changes of the polymer, induced by the osmotic action of the excipient.