The invention comprises an apparatus meant to be carried by a user for dosing a drug, a method for dosing drug and a wireless remote control for a drug pump. The apparatus comprises a drug pump (1), a computer (9), which is arranged to control the pump, control units (10) for transmitting control functions from the user to the computer, indicators (11) for transmitting information from the computer to the user, a measuring device (12), which is arranged to produce information about the physical activity of the user, means of calculating the amount of drug needed by the user based on the information produced by the measuring device.