Abstract
About 18 080 cases of suspended "driving under the influence alcohol" are analysed for ethanol annually at our laboratory. More than 12% of the drivers stated that they had taken one or several drugs, either with or without alcoholic beverages. In about 10% of these cases ( 1.2% of the total) chemical analysis of samples of blood and/or urine were requested as abuse was suspected. In about half of these instances, blood or urine samples were not sent to the laboratory, or were sent in insufficient amounts.