近年來，口服固體劑型可藉由配方設計以改良藥物之釋放及吸收。藥物控制釋放製劑具有多項之優點，除了可以維持藥品的血中濃度以提高治療效率外，也可減少投藥次數以改善傳統口服劑型的投藥之不便性，所以藥物製劑配方與技術對於藥物釋放影響之各項研究就顯得相當重要。 本實驗使用治療消化性潰瘍之藥物雷貝拉唑 (Rabeprazole) 及治療膀胱過動症之藥物奧昔布寧 (Oxybutynin) 作為模式藥物，製備不同比例高分子之處方製劑和不同比例之腸溶包衣包覆，以探討在製劑中控釋高分子與腸溶包衣材質比例對 Rabeprazole 及 Oxybutynin 釋放之影響；並探究腸溶包衣對 Rabeprazole 延遲釋放劑型化學安定性之影響。 研究結果顯示，在相同 pH 值之溶離試驗下，Rabeprazole 隨著內包衣層厚度的增加而降低其溶離速率。而在酸性的溶離液底下，若腸溶包衣層包覆足夠，就可保護主成份不受酸性環境的影響而產生降解。 在 Oxybutynin 的部分，親水性高分子的黏度及使用量的選擇是主要影響藥物核心釋放速率的關鍵。而在包衣包覆組成中調整羥丙基甲基纖維素與腸溶包衣高分子之比例，在溶媒 pH1.2 中亦可達到不同之釋放速率。由上述研究內容顯示，應用腸溶包衣系統的方式來製備具有控制釋放效果的口服 Rabeprazole 和 Oxybutynin 製劑是確實可行的。 In recent years, scientific and technological advancements have been made in the development of controlled drug delivery system. Controlled drug delivery technology has many advantages, such as improve effectiveness, convenience and reduce side effects. It also helps to improve quality of life. In order to obtain optimum formulation to ensure efficacy and safety profiles, the effect of formulation variables on drug release and stability are crucial. Rabeprazole and oxybutynin are used in the present study as the model drugs. Formulations with different polymer amount and enteric coating ratios were designed to evaluate their effects on drug release as well as chemical stability. The results demonstrate rabeprazole dissolution rates decreased with the increased in inner coating level. As in the acid dissolution media, no significant degradation was observed if enough enteric polymer has been coated. For oxybutynin, the hydrophilic polymer viscosity and amount added can affect the drug release rates. Adjusting the ratios of HPMC and Eudragit L100-55 amounts contributed to different release rates in pH1.2 medium. The study clearly shows that the application of enteric coating systems to obtain optimum release rates of rabeprazole and oxybutynin is feasible.
