RESUMO
A virtual increase in the number of patients undergoing immunosuppressant therapy and those suffering from AIDS has created a unique class of population suffering from virulent uveitis and retinopathies. A very common pathogen implicated in retinopathy in such patients is the cytomegalovirus (CMV).
Assuntos
Retinite/tratamento farmacológico , Uveíte/tratamento farmacológico , Animais , Contraindicações , Citomegalovirus/efeitos dos fármacos , Sistemas de Liberação de Medicamentos/efeitos adversos , Sistemas de Liberação de Medicamentos/métodos , Humanos , Retinite/terapia , Retinite/virologia , Uveíte/terapia , Uveíte/virologiaRESUMO
Scleral implants of indomethacin with sodium alginate as carrier were fabricated and evaluated for various physico-chemical properties such as uniformity of thickness, weight, drug content, surface pH, percent dissolution and water up-take capacity (swelling index). The effect of drug particle size, polymer concentration, drug loading, plasticizer concentration, and effects of physical reinforcement (freeze-thawing for 3 and 6 cycles) and chemical cross-linking with calcium chloride, on the in vitro drug release characteristics were evaluated. Selected batches of the implants were subjected to pharmacodynamic studies, after scleral placement, in uveitis induced (intravitreal injection of Bovine Serum Albumin (BSA)-50 micrograms/ml) rabbit eyes. The release of indomethacin from the prepared implants followed predominantly matrix diffusion kinetics. Swelling and moisture absorption/loss studies correlated well with the in vitro release studies. The pharmacodynamic studies showed a marked improvement in the various clinical parameters (congestion, keratitis, flare, clot, aqueous cells and synechias), in the implanted eye when compared to the control eye in the rabbits.
Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/farmacocinética , Indometacina/administração & dosagem , Indometacina/farmacocinética , Esclera , Alginatos , Animais , Fenômenos Químicos , Físico-Química , Reagentes de Ligações Cruzadas , Portadores de Fármacos , Implantes de Medicamento , Congelamento , Ácido Glucurônico , Ácidos Hexurônicos , Concentração de Íons de Hidrogênio , Tamanho da Partícula , CoelhosRESUMO
Indomethacin-nicotinamide solid dispersions were prepared by fusion method. Drug-carrier interaction in the liquid and solid states were studied using phase solubility data and differential scanning colorimetry (DSC). DSC revealed the formation of an eutectic mixture of indomethacin and nicotinamide. Tablets and capsules, formulated from the solid dispersions showed significantly better dissolution and enhanced absorption rate in human volunteers, compared to commercial capsule of indomethacin.