A disposable needleless injection device includes an integral unit that is dimensioned
and arranged to be grasped in the hand of a user. The system is spring-loaded and
is manufactured and shipped with the spring in a pre-cocked condition. An integral
ampule is fillable by manipulation of a thrust rod/shaft which extends longitudinally
through the device and is able to be grasped by a user. Once the unit is filled
with a selected medication, it is held proximate the skin in order to inject the
selected dosage. The unit is constructed from a maximum of eight component parts
and is assembled in a matter of moments by unskilled personnel.
