ABSTRACT
INTRODUCTION For most formulations used by the patient population, the oral form will always be preferred considering the relative ease of self-administration of the drug product. In general, the oral formulation follows similar “digestive” processes, starting with degradation/dissolution of the drug product down to the absorption of the active moieties. However, as the absorption process of oral drugs is limited or influenced by intrinsic factors, some of them may not go through drug release and dissolution steps and probably not reach the systemic circulation. In consequence, the absorption process of the parent drug and/or its related metabolites will differ between drug products as well as between different formulations of the same drug (e.g., immediate-release vs. extended-release).
