A circuit arrangement for operating a discharge lamp, wherein the circuit arrangement comprises a commutation device, which has an input which is coupled to a DC source, and has an output which can be coupled to a discharge lamp. The commutation device is designed in such a way that it couples the DC source to the output, and the polarity at which the DC source is coupled to the output can be commutated by a control device. The control device has a sync input, and the polarity of the DC source is commutated in synchronism with sync pulses of a sync signal which can be applied at the sync input. The control device has a measuring input, which is coupled to a measuring device which is designed to provide a measured value which is a measure of the size of electrode peaks. The control device suppresses at least one commutation if the measured value overshoots or undershoots a predetermined threshold value.