Since their introduction in the 1960s, benzodiazepine drugs have been widely prescribed for anxiety states and insomnia. Despite the initial hopes for these drugs being non-addictive and not producing tolerance, recent work has shown that there is a well defined withdrawal syndrome (Hallstrom & Lader, 1981; Petursson & Lader, 1981; Tyrer et al, 1981; Tyrer et al, 1983) and that tolerance has also been shown to occur (Aranko et al, 1983; Aranko et al, 1985). There has been widespread concern about these effects. The British National Formulary advocates that “used as hypnotics routine prescribing especially in hospitals is undesirable, and ideally they should be reserved for short courses of treatment in the acutely distressed” and that they should be discontinued as soon as possible. Indeed the Royal College of Psychiatrists' statement on benzodiazepine prescribing and the Committee on Safety of Medicines have recommended that their use as hypnotics should be considered only when the condition is severe, disabling or subjecting the individual to extreme distress. Tyrer & Murphy (1987) have recommended that these drugs are best used for no longer than two weeks in regular dosage.