Introduction of sustained release opipramol dihydrochloride matrix tablets as a new approach in the treatment of depressive disorders.

Opipramol 2-HCl (OP) is used for therapy of general somatoform and anxiety disorders. Conventional tablets in the market contain 50 mg OP to be used once or up to three times a day in effective treatment of depression in mild. In case of serious depressive disorders, OP may be administired up to 300 mg a day. Decrease in frequency of high dose administration via sustained drug release would reduce incidence of symptoms of intoxication in long-term use of OP. With this aim, OP matrix tablets containing 100 mg were prepared by direct compression method to be used once a day to provide patient compliance and constant blood level, consequently to decrease side effects. Two concentrations of polymers (10% and 20%): hydroxypropylcellulose (HPC) and hydroxypropyl methylcellulose (HPMC), sodium alginate (NaAlg), xanthan gum (XG) and Carbopol(®)941 (C941) were used in preparation of matrix tablets. Drug release study were performed in distilled water, pH1.2 HCl buffer and pH7.4 phosphate buffer solutions according to the Method II in USP 29. Two commercial tablets containing 50 mg OP available in Turkish market were used for comparison. Kinetic models of release patterns from tablets were evaluated. Drug release was displayed slower to faster pattern in order of formulations containing C941, HPMC and HPC. Drug release was significantly faster in tablets of 10% polymers than those of 20%. NaAlg and XG were insufficient to sustain drug release. The most sustaining drug release effect at the lowest polymer concentration was obtained with C941. Drug release from matrix tablets containing 10% C941 was determined as 58.2%, 52.4 and 57.0% in related dissolution mediums above after 8 hours, respectively. However, HPMC and HPC sustained drug release at 20% concentration. As a result, Carbopol® 941, HPMC and HPC can be suggested as suitable to prepare matrix tablets of OP.

A new approach for preparing a controlled release ketoprofen tablets by using beeswax.

Solid lipid ketoprofen micropellets (SLKM) at different drug/beeswax ratios [(1:1) and (1:2)] were prepared by emulsion congealing technique and then compressed into tablets. Ketoprofen in solid state was incorporated into the melted beeswax at 90 degrees C and the mixture was emulsified in the hot aqueous Tween 80 solution by stirring at a constant rate. The SLKM were obtained by cooling the coarse emulsion down to room temperature and filtering. Drug entrapment efficiency and particle size analysis by laser diffractometry (LD) were determined, and existence of a drug-lipid interaction was investigated by differential scanning calorimetry (DSC) on the SLKM, before being compressed into the tablets by direct compression method. Finally, in vitro release studies were performed and the release kinetics of the waxy tablets were calculated. A commercial ketoprofen retard tablet (reference: Profenid Retard 200 mg) was also examined to compare the release properties. While the data obtained from DSC were indicating absence of drug-lipid interaction in the SLKM, it was determined that 28.62% (+/-2.08), 38.60% (+/-1.91) and 47.00% (+/-1.82) of ketoprofen was released from the tablets containing (1:2) and (1:1) SLKM and Profenid Retard 200 mg in pH 7.4 phosphate buffer solution after 8 h, respectively.

Evaluation of honey locust (Gleditsia triacanthos Linn.) gum as sustaining material in tablet dosage forms.

In this study, honey locust gum (HLG) obtained from Gleditsia triacanthos (honey locust) beans was investigated as a hydrophilic matrix material in the tablets prepared at different concentrations (5% and 10%) by wet granulation method. Theophylline was chosen as a model drug. The matrix tablets containing hydroxyethylcellulose and hydroxypropyl methylcellulose as sustaining polymers at the same concentrations were prepared and a commercial sustained release (CSR) tablet containing 200 mg theophylline was examined for comparison of HLG performance. Physical analysis on CSR tablet, matrix tablets and their granules before compression were performed. According to the results obtained from dissolution studies in distilled water, pH 1.2 HCl buffer and pH 7.2 phosphate buffer, no significant difference was found between CSR tablet and the matrix tablet containing 10% HLG in each medium (P > 0.05) and these tablets showed zero-order kinetic model in all the mediums.