The present invention relates to a liquid drug medical device for use with a syringe having a syringe tip with a distal end with a laterally projecting lip having an external diameter D2, and a medicinal vial with a rubber stopper, the device including an adapter for snap fitting onto the vial and including a hollow puncturing member rigidly connected to the adapter for puncturing the rubber stopper on snap fitting the adapter on the vial, the device further including a short elastomer tubing in flow communication with the puncturing member, and having a distal end with a nominal internal diameter D1<;D2 and of at least 3mm for being sealingly stretched over the syringe's laterally projecting lip for effecting fluid communication between the syringe and the medicinal vial.