Theoritical Uses of Pramipexole dihydrochloride in Parkinson's Resistance Depression

Pramipexole dihydrochloride monohydrate is an antiparkinson’s agent which is known as dopamine D2 receptor agonist. It is structurally different from the ergot-derived drugs, e.g. bromocriptine or pergolide. Pramipexole is designated chemically as (S)-2-Amino-4, 5, 6, and 7-tetrahydro-6-(propylamino) benzothiazole and has the molecular formula C10H17N3S. It comes under class I of Biopharmaceutical Classification System. The purpose of this study was to develop and evaluate pramipexole dihydrochloride monohydrate extended release tablets by wet granulation method using different proportions of polymers and binder. Pre-formulation studies were done initially and the results were found to be within the limits. All the mentioned batches were prepared and granules were evaluated for pre-compression parameters such as loss on drying, bulk density, tapped density and compressibility index. Tablets were evaluated for weight variation, thickness, hardness, friability; disintegration time and assay were found to be within the limits. In vitro dissolutions were performed with 0.05M 6.8 PH phosphate buffer and effect of various polymers were explored. Final selection of formulation was based on dissolution profile, from dissolution studies formulation 9 showed 80% drug release within 20 hours, so it will be compared with innovator. Similarity and difference factors which revealed that formulation (F 9) containing HPMC K 200, Eudragit L100 and binder are most successful as it exhibited in vitro drug release that matched with innovator product. In vitro drug release profile reveals that with increased concentration of Eudragit L 100. Accelerated stability studies were performed for the optimized batch which indicated that there were no changes in drug content and in vitro dissolution.