Benzodiazepines and antidepressants are frequently used for the treatment of anxiety disorders, nevertheless low rates of remission and high rates of nonresponse are reported with their use. Fourty to 70% of patients with anxiety disorders fail to respond and more remain partly symptomatic after treatment, therefore there is a need for novel therapeutic strategies for refractory patients.

A small number of studies have been conducted in order to investigate the efficacy of 2nd generation antipsychotics for generalized anxiety disorder (GAD). Risperidone, olanzapine, aripiprazole, quetiapine and ziprasidone have proven to be effective and safe for the treatment of generalized anxiety disorder, either as augmentors of selective serotonine reuptake inhibitors (SSRI's) or as monotherapy.

However, definite conclusions cannot be drawn based on the small number of studies, the fact that they were mostly open-label and had small sample sizes. The efficacy and safety of 2nd generation antipsychotics in GAD needs to be further investigated with randomized, double-blind, placebo controlled trials.