Document Type : Original Article
Islamic Azad University,Pharmaceutical Sciences Branch
Department of Pharmaceutics, Pharmaceutical Sciences Branch, Islamic Azad University (IAUPS), Tehran, Iran
Hakim Pharmaceutical Company, Tehran, Iran (R&D Expert)
The main aim of this study was to prepare and evaluate the extended - release system of an anxiolytic substance. Alprazolam is a short-acting benzodiazepine with general
properties similar to those of diazepam. Our studies focused on the development of extended drug delivery system based on Hydroxy Propyl Methyl Cellulose (HPMC 4000cps) as retard agent and polyvinylpyrrolidone (PVP k30) as binder using factorial design. All formulations were prepared according to wet granulation method and were compressed after lubrication using 7.0 mm dip concave punch with tablet weight of 100 mg. The humidity of granules was selected below 3 percent for obtaining to suitable flowability and compression process. Physical tests such as weight variation, friability, hardness, and thickness tests were carried out.The variables were studied based on 22 factorial design procedure. All prepared matrix tablets were evaluated for physicochemical evaluation and drug content. In vitro release study of matrix tablets for all formulations has shown that HPMC was the main component in retardation of alprazolam in the dissolution medium. The optimum formulation (30% HPMC 4000 and 10% PVP) with suitable release profile according to criteria of United State Pharmacopoeia was selected for stability studies, according to ICH guidelines. For stability tests, the content of drugs did not show any change after 3 months during accelerated stability test. The release profile of this formulation was found acceptable as recommended by USP. The release studies have shown that swelling, swelling/erosion, and disentanglement/dissolution were the most important mechanisms that could affect the release profile.