A drug delivery device is provided comprising a container, a first product and a second product. The device is configured to mix the first product and the second product with each other within the container for forming a drug mixture. The device is further configured for dispensing the drug mixture. The device comprises a mixing member. The device is switchable from a first state, in which the first product and the second product are separated, into a second state, in which the first product and the second product are mixed. The mixing member is configured to exert a force onto the container in order to move the container to mix the first product and the second product with each other. Furthermore, a method for maintaining a predetermined property of a drug mixture to be dispensed from a drug delivery device is provided.