A medical system for monitoring a measured value of a patient characterizing blood clotting and/or for setting a medication that influences blood clotting for a patient in a home environment, has a device for acquiring measured values of the patient relating to blood clotting, a device for transmitting the measured values to a system central, a device for interrogating the measured values, and a reception device at a monitoring person. The system central has a memory for the measured values, an analysis device for the measured values by comparing the measured values to stored reference values, an alarm generator which generates an alarm signal upon a recognition of predetermined conditions, and a routing device for forwarding the alarm signal to a reception device of a person to be alerted in a process chain.