A solid preparation 1 comprises a drug-containing unit 2 containing a cationic drug, and a gel-forming layer 4, containing an anionic polymer, for covering the drug-containing unit 2 and forming a gel with absorbing water, and optionally an intermediate layer 3 interposed between the drug-containing unit 2 and the gel-forming layer 4. The solid preparation 1 improves the elution property of the drug by incorporating an acidic component (such as tartaric acid or citric acid) into the intermediate layer 2 and/or the intermediate layer 3. The gel-forming layer 4 may comprise a carboxyvinyl polymer and a polyvalent metal compound. The gel-forming layer 4 may be covered with a surface layer (anti-adhesive layer) 5.
固体制剂 1 包括含有阳离子药物的含药单元 2 和含有阴离子聚合物的凝胶形成层 4,凝胶形成层 4 用于覆盖含药单元 2 并形成具有吸
水性的凝胶,还可选择在含药单元 2 和凝胶形成层 4 之间设置中间层 3。固体制剂 1 通过在中间层 2 和/或中间层 3 中加入酸性成分(如
酒石酸或
柠檬酸)来改善药物的洗脱特性。凝胶形成层 4 可由羧基
乙烯聚合物和多价
金属化合物组成。凝胶形成层 4 可覆盖表面层(防粘层)5。