Prefilled ampoule-syringe of unitary dose

摘要

A prefilled ampoule-syringe of unitary dose comprises an ampoule being closed at one of its ends, the other end being open. The ampoule further comprises a narrowed zone. A hollow capsule is arranged at top of the opening of the ampoule. This capsule is connected to a movable stopper means comprising a stopper head and a hollow cylindrical member having a radial channel and a peripheral rim. This rim acts as a retention member during the storage and as a piston ring during the injection. In order to avoid the loss of its elasticity, the rim is located within a belt of enlarged diameter downstream from the narrowed zone during the storage.