Controlled-flow needle injection device comprising a needle or cannula (1) with standard coating for performing nerve blocks a first independent line for administering local anaesthetic (4) connected to a high-pressure syringe and a second independent aspiration line (5) connected to a mechanical aspiration syringe characterised in that it comprises a manual flow control element (10) having a first aspiration position (11) that enables the connection between the needle or cannula (1) and the aspiration line (5) a second administration position (12) that enables the connection between the first independent administration line (4) and the needle or cannula (1) and a third neutral position (13) without administration or aspiration and wherein by sliding it switches from a neutral position (13) to an aspiration position (11) and from there to an administration position (12) by means of continuous pressure exerted by the anaesthesiologist, returning to the aspiration position (11) when said pressure is no longer exerted towards the administration position (12) and wherein the pressure exerted on the flow controller (10) is exerted only by the anaesthesiologists dominant hand.