An appliance is provided for negative-pressure therapy of wounds on the human or animal body in which, on the one hand, a substance is delivered to a wound bed (W) and, on the other hand, fluids, in particular an exudate and the delivered substance, are aspirated from the wound bed by negative pressure. The appliance has a suction pump housing, with a suction pump arranged therein for aspirating the fluids from the wound bed (W), and a fluid collection container for collecting the aspirated fluids. Moreover, the appliance has a first measuring device and a second measuring device. The first measuring device serves to determine the quantity of the aspirated fluids, and the second measuring device serves to determine the quantity of the substance delivered to the body.