Central nervous system depression
Central nervous system depression (or CNS depression) is a nervous system disorder characterized by a severely impaired physiological state in which patients may exhibit decreased rate of breathing, decreased heart rate, and loss of consciousness; in extreme cases, CNS depression can possibly lead to coma or death. == Causes == Central nervous system depression is generally caused by the improper or excessive use of depressant drugs such as opioids, barbiturates, benzodiazepines, general anesthetics, anticonvulsants, and certain sleep medications.
Source: Wikipedia — Central nervous system depression (CC BY-SA 4.0)