An implantable drug infusion pump for delivering drug therapy is made more reliable and its performance improved by monitoring drug pump temperature. Monitoring pump temperature can also provide for temperature-related drug therapy modification.A pump temperature sensor is read by the infusion pump's microprocessor. Pump temperature data is stored in pump memory for later access by a remote controller. A simple thermistor or semiconductor temperature sensor can provide fast and reliable temperature monitoring of the pump and/or of a patient by reading the temperature sensor's value and calculating a temperature therefrom.