A portable, hand-held, battery-powered device designed to accept a pharmaceutical-containing cartridge (not included) and intended to be used by a patient to subcutaneously inject a dose of the pharmaceutical agent via a replaceable needle. The cartridge is inserted into the device and is replaced once the pharmaceutical is exhausted; the needle is replaced for each administration. The device includes an electronic display and may be capable of a variety of dose-recording functions. This is a reusable device.