The present invention relates to a needleless injection device (1) comprisinga reservoir (3), obturated by an upstream stopper (4) and a downstream stopper(5) between which a liquid active principle (6) is accommodated, and a receptacle(7) comprising at least one injection conduit (8), said receptacle comprisinga cavity (10) whose height is equal to the distance travelled by the downstreamstopper before each injection conduit is opened, - the height of the cavity inmillimetres being between a minimum height and a maximum height, respectivelydefined by the following relationships, • minimum height = 3, •maximum height = 15 x exp. (-(V/9)
