Modes of awareness associated with use of sedatives

These drugs alter behaviour by acting on the central nervous system and high doses produce sleep. There is a hypnotic effect and relief from anxiety and stress, resulting in psychological dependence. Initially there may be euphoria but tolerance builds up and larger and larger doses are needed for the same effect. Eventually these may lead to side effects perhaps resulting in death. Withdrawal symptoms include insomnia, anxiety and seizure, and may also be life-threatening. Barbiturates act like alcohol and also enhance the effects of alcohol, so that the two together can be very dangerous. They may be originally prescribed as tranquillizers, although they have a high placebo effect (people reporting immediate relief from stress before the drug has had time to act).