Psychoactive medicines, such as painkillers (opioids), sedatives (benzodiazepines), antidepressants and antihistamines can have sometimes considerable effects on the capabilities of drivers.
Uaireanta bíonn éifeachtaí suntasacha ag cógais shícighníomhacha, ar nós pianmhúcháin (substaintí óipiam), támhacháin (beinsidéasaipín), frithdhúlagráin agus frith-hiostaimíní ar inniúlachtaí na dtiománaithe.