Abstract
The fundamental assumptions of the traditional deterministic linear models are those of continuous and differentiability of physical quantities involved in drug release processes. However, these assumptions are in reality contrary to the evidence given by the complexity of the drug release process. Thus, we will consider that, at mesoscopic scale, the drug release mechanisms are based on the assumption that the drug particle movements take place on continuous, but non-differentiable curves (fractal curves), for which a Weibull type equation results. In this approach, analyzing some experimental data, information on the drug release mechanism and system complexity are obtained. Keywords: fractal, drug release mechanism, polymers microparticles, mesoscopic scale