A valve assembly (10) is provided which includes a housing (11) having an inlet end (20) and an outlet end (22) and defining a fluid channel (18) and a central chamber. A dissolvable valve member is positioned to obstruct flow through the channel within the chamber. The dissolvable valve member (16) is formed of a material which is dissolvable at a predetermined rate upon contact with a preselected fluid. The preselected fluid is selected from the group consisting of blood, urine, saline and antimicrobial solutions. The dissolvable valve member can be formed from a fluid soluble glass or a starch based material.
