107 reference is additionally made to the teaching in said application which is incorporated herein by reference a container in the form of an ampoule 2 is accommodated in a pump casing 1 the ampoule 2 is filled with insulin a delivering appliance in the form of a piston 6 is accommodated in the ampoule 2 such that it is linearly slidable in a feed direction towards an outlet 3 of the ampoule the piston 6 is advanced by a driven member 7 formed as a threaded rod pressing on a rear surface of the piston 6 the driven member 7 is part of a spindle drive 8 which is formed with two telescopic stages with respect to the piston drive the invention is not however restricted to this when the piston 6 is advanced along an sliding axis v insulin is delivered via a catheter 4 connected to the outlet 3 and an infusion needle 5 fixed to the front free end of the catheter 4 together the ampoule 2 outlet 3 catheter 4 and needle 5 may be thought of and referred to as comprising a fluid guiding system in order to set a defined base pressure in the ampoule 2 a valve 25 is.