特性:
1.只增加10-20mg重量
2.採用不含水的溶劑,所以不需經固封
3.可自動化操作
4.無熱量、無味道,不易被兒童誤食
5.可保留錠劑原有外形
6.有伸縮性和彈性,所以不易破裂或龜裂
7.對錠劑之崩散時間和溶離速率影響不大
8.採用有機溶媒,十分安定、不長微生物
9.可經設計成腸溶製劑或快溶製劑
10.包衣微粒可混合適當賦形劑後製備成錠劑
目的:
1.使有效成分不易受潮變質,有利於藥物保存
2.掩蓋藥物不良味道
包衣配方:
(非)水溶性膜衣材料---高分子聚合物+塑化劑+溶媒
可再添加界面活性劑、著色劑、阻光劑、矯味劑、光澤劑
中華藥典:
膜衣錠—膜衣錠可由含有水溶性或分散性物質,如羥丙甲基纖維素、甲基纖維素、羥丙纖維素、羥甲基纖維素鈉及乙酸酜酸纖維素與聚乙二醇之混合物等,以非水性或水性溶劑作成溶液為之,當溶劑蒸發除去後,即留一薄膜直接黏附於錠劑之外表,而仍維持原有錠劑之外型,溝線或識別符號等。
Ansel原文書:
Film-coated tablets are compressed tablets coated with a thin layer of a polymer capable of forming a skin-like film. The film is usually colored and has the advantage over sugarcoatings in that it is more durable, less bulky, and less time-consuming to apply. By its composition, the coating is designed to rupture and expose the core tablet at the desired location in the gastrointestinal tract.