At the beginning of therapy with opioids the physician has to fulfil his duty to inform the patient of any possible dangers of treatment. From the medical point of view, driving must be prohibited until a stable opioid dosage is reached. Any changes in dosage (increase, reduction), change of the opioid and poor general condition independent of the opioid therapy must result in prohibition of car driving. Continuous control of the therapy with documentation is a duty of the physician. The written documentation should include the patients' physical and mental condition, side effects and the therapeutic result. From the medical point of view, driving can be possible when dosage treatment and general condition remain stable. In any case, the doctor has to remind the patient of the responsibility of critical self-examination. In doubt, special performance investigation should be taken into consideration.