Preparation and release study of Levetiracetam 500 mg extended release tablet by using combination of hydrophilic and hydrophobic polymers.

Levetiracetam as an Anti-epileptic drug with exclusive mechanism of action is accepted by the USA Food and Drug Administration as an adjunctive therapy in treating epilepsy in young adults. The purpose of this project is the design and formulation of prolonged release of levetiracetam using two types of retarding agent such as Hydroxyl Propyl Methylcellulose (HPMC K4M) and xanthan Gum, as well as a fatty matrix of cetyl alcohol. In addition, by manufacturing this product, it is possible to make a domestic production of this form of medicine, importing this form of medicine into the list of generic drugs of Iran. Pre-formulation studies such as compaction of granules, compressibility and the ability of powder to flow were observed prior to formulation. The percentage of excipients in the formulation such as HPMC K4M, PVP k30, Mg-st, were considered as variables to examine rate of release and physical properties in Factorial design method. In optimization process, xanthan gum is added alone to formulation abc obtaining formulation X, in addition, xanthan gum in combination with cetyl alcohol is used to obtain formulation F,then release studies were evaluated.
According to data obtained from release profiles, prepared tablets with both hydrophilic and hydrophobic retard agent (HPMC K4M 30%, xanthan gum 2%, cetyl alcohol 2%) have revealed similar profile of release the active agent according to USP limited range. Furthermore, the release studies have shown that swelling, swelling/erosion and dissolution were the most important mechanisms that could affect the release profile. It also suggested that the percentage release of formulation F was followed Higuchi model