A method and composition for effecting chemical necrosis of a tissue lining of a mammalian body cavity, particularly a uterine endometrium, by delivering a caustic tissue necrosing composition, e.g., a silver nitrate and dextran paste, to the tissue to be necrosed and allowing the paste to remain in contact with the target tissue for a period of time sufficient to chemically necrose substantially the entirety of the tissue lining, and then contacting the caustic composition with a deactivating agent, e.g., an aqueous sodium chloride solution, thereby rendering the caustic composition non-caustic, and then rinsing the cavity. Compositions and methods for delivering medicaments are also disclosed.