A fluid dispenser device having a body (1), a fluid reservoir (3) containing two half-doses, a dispensing mechanism that dispenses a half-dose of fluid upon actuation, and an energy accumulation mechanism (50, 51, 55) that accumulates energy in the hand of the user and released suddenly so that each of the half-doses is dispensed in full. The dispensing mechanism includes a dispensing member (8) mounted to slide in the reservoir (3) for dispensing the fluid, an actuating element (5) mounted to move between a rest position and an actuating position and on which the user exerts an actuating force to move the dispensing member (8) inside said reservoir (3). The actuating element is mounted to move in a direction substantially transverse to the direction in which the dispensing member (8) moves, and a dose-splitting mechanism (7, 12) dispenses a half-dose of fluid each time the dispensing mechanism is actuated.