FIELD : medicine. SUBSTANCE : invention relates to a medical technique, namely to expectorating device (1). Device comprises body (3), chamber (5) formed in body (3), mouthpiece (7) communicating with chamber (5) and protruding from body (3). Device includes solenoid valve assembly (9) for opening or closing chamber (5) at a predetermined frequency. Solenoid valve assembly (9) comprises plunger (13) capable of reciprocating movement. Electromagnetic valve assembly (9) comprises coil assembly (17) disposed around plunger (13) and check valve (19) located at the free end of plunger (13). Solenoid valve assembly (9) includes a holding member for holding solenoid valve assembly (9) in the closed position. Retaining member for holding solenoid valve assembly (9) in the closed position is permanent magnet (15), arranged around plunger (13) to provide a holding force for holding check valve (19) in engagement with airflow outlet (21), or a spring for pushing check valve (19) towards airflow outlet (21). Device comprises sensor (29) for measuring the pressure in chamber (5) and generating a control signal when the pressure in chamber (5) reaches a predetermined pressure level. Device includes a control unit for controlling the electromagnetic valve assembly (9) based on the control signal received from sensor (29). Control unit turns on or off coil assembly (17) at a predetermined frequency and controls the direction of the current passing through coil assembly (17), based on the control signal received from sensor (29). EFFECT : expectorating device for prevention of the collapse of the patient' s airway caused by a rapid decrease in pressure. 7 cl, 4 dwg