The factors adversely affecting traffic safety include a constantly increasing number of vehicles resulting in heavy traffic, then ageing population and increasing psychic stress for modern man. The necessity of psychic well-being is more urgent particularly for drivers – and sometimes they evoke it by various ways. Apart from medicaments taken by them in an inexpert way we can encounter taking alcohol, drugs and other xenobiotics particularly in road traffic accidents. Though detection of these substances is possible, it is very often cost-demanding. Assessment of their impact is professionally difficult particularly if there is a concurrent effect of various substances. Long-term research demonstrates that the majority of road users in fatal traffic accidents were under the influence of a certain xenobiotic. In this article the authors briefly analyze subject problems and possibilities related to solving them.

Key words: alcohol – road safety – medicaments – impairred driving – toxicological analysis – xenobiotics