A pharmaceutical composition for treating or ameliorating a disease such as cancers or overactive bladder by inhibiting acetylcholine receptor activity is disclosed. The pharmaceutical composition comprises an effective amount of a sesame extract and a pharmaceutically acceptable carrier. The pharmaceutical composition may further include a chemotherapy agent.一種經由抑制乙醯膽鹼受器而治療或改善諸如癌症或膀胱過動症之疾病病況的醫藥組合物,其包含一有效量之芝麻萃取物及其藥學上可接受的載體。此醫藥組合物中還可更包含一化療藥劑。