Anxiolytics and sedative/hypnotics dependence.

Abstract

Anxiolytics and sedative/hypnotics are commonly used drugs. Benzodiazepines have largely replaced barbiturate and non-barbiturate anxiolytics and sedative/hypnotics as they are as effective and safer. Experiments in laboratory animals have shown that chronic administration of benzodiazepines tested to date can induce physical dependence. The severity of the withdrawal syndrome is clearly related to the dose, duration of administration and elimination rate of the drugs. It is now also clear that high doses of barbiturates and benzodiazepines can induce physical dependence in humans. In addition, a withdrawal syndrome after discontinuation of chronic benzodiazepine therapeutic treatment, with and without tolerance, has been well characterized. Symptoms may resemble those of anxiety or 'rebound' phenomena but some are typical of withdrawal. A relationship between benzodiazepine discontinuation and self-administration has been well documented. Negative reinforcement associated with a reduction of withdrawal symptoms may play a role supporting persistent benzodiazepine use.