The device (A) has control devices (2A, 2B) for controlling a treatment unit (1) to perform extracorporeal blood treatment and to initialize the treatment, respectively. An internal communication unit (15) e.g. mobile telephone unit, communicates with an external communication unit (C) i.e. mobile telephone, over a communication network (B) e.g. mobile radio network. The unit (15) and the device (2B) are designed such that the device (2B) is activated after receiving an initiation code e.g. short message, from the unit (C) so that the unit (1) is initialized to perform the treatment. An independent claim is also included for a method for initializing blood treatment.