A valve assembly is provided which includes a housing having an inlet end and an outlet end and defining a fluid channel and a central chamber. A dissolvable valve member is positioned to obstruct flow through the channel within the chamber. The dissolvable valve member 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.
