Benefits and Liabilities of Benzodiazepines and Z-Drugs: What We Know and What We Don't Know.

Benzodiazepines, first introduced in the 1960s as effective and safer alternatives to barbiturate sedative-hypnotics, are now widely viewed as having a high risk of overdose, abuse, addiction, and "dependency". These beliefs are contrary to extensive scientific evidence. Systematic research has shown that prescribed benzodiazepines are not prone to tolerance, dose-escalation, abuse, or addiction. Benzodiazepine abuse and overdose fatalities occur largely in the context of established polysubstance abuse. They are as effective as antidepressants and have fewer adverse effects but similar withdrawal syndromes. Major adverse effects are impairment of coordination, memory, and cognition, of most concern in older populations, and increased risk of motor vehicle accidents, especially when used along with alcohol. Most patients can be withdrawn from benzodiazepines without major difficulty using clinician supportiveness and flexible tapers. Reports of severe adverse reactions to benzodiazepines and of severe, prolonged difficulties withdrawing from them have not been subjects of systematic study and are poorly understood. In summary, the literature supports use of benzodiazepines on par with antidepressants for anxiety disorders, and for benzodiazepines and z-drugs for short-term mitigation of insomnia.