A machine for the preparation of pharmaceutical products including at least one dosing chamber (2)； a containment lining (27) that extends around at least part of the dosing chamber (2)； a pneumatic ventilation device (31) for generating a first air flow to the dosing chamber (2) and at least a second air flow to the containment liner (27)； and a control unit (54) for selectively controlling the pneumatic ventilation device (31), and consequently said air flows, so that the containment lining (27) has a lower pressure inside it than an existing pressure inside the dosing chamber (2) and that a pressure existing in the environment outside the containment lining (27) itself； and where the dosing chamber (2) is provided with a mixer assembly (13) to prepare at least one pharmaceutical product and the containment lining (27) extends around the dosing chamber (2) so as to define a first containment chamber (23, 30) and a second containment chamber (16) for a storage tank (14) for a plurality of packages (15) containing pharmaceutical products and / or diluents； the pneumatic ventilation device (31) including a first feed circuit (33) to feed the first air flow through the dosing chamber (2), a second feed circuit (45) to aspirate the second air flow of the first containment chamber (23, 30), and a third supply circuit (48) to feed a third air flow through the second containment chamber (16).Una máquina para la preparación de productos farmacéuticos incluyendo al menos una cámara de dosificación (2)； un revestimiento de contención (27) que se extiende alrededor de al menos parte de la cámara de dosificación (2)； un dispositivo de ventilación neumática (31) para generar un primer flujo de aire a la cámara de dosificación (2) y al menos un segundo flujo de aire al revestimiento de contención (27)； y una unidad de control (54) para controlar selectivamente el dispositivo de ventilación neumática (31), y en consecuencia dichos flujos de aire, de modo que el revestimiento de c
