Atypical antipsychotics in the treatment of delirium.

Delirium is common in all medical settings. Atypical antipsychotics are increasingly used for the management of delirium symptomatology but their effectiveness has not been systematically studied. The aim of the present study was therefore to provide an up-to-date review on the use of atypical antipsychotics in the treatment of delirium. A search was conducted of the databases of MEDLINE, PsycINFO and EMBASE from 1997 to 2008 for English-language articles using the key words 'delirium' and the names of all the atypical antipsychotics. A total of 23 studies were used for this review. Fifteen of the studies were single-agent trials. Four studies were comparison trials, including one double-blind trial, and four studies were retrospective, including three comparison studies. All studies reported improvement of delirium symptomatology after the administration of atypical antipsychotics. No study included a placebo group. Other limitations included sample heterogeneity, small sample size, different rating scales for delirium, and lack of adequate controls. The improvement in delirium was observed within a few days after treatment initiation and the doses given were relatively low. Atypical antipsychotics were well tolerated, but safety was not evaluated systematically. Atypical antipsychotics appear to be effective and safe in symptomatic treatment of delirium but the evidence is limited and inconclusive. There are no double-blind, placebo-controlled studies assessing the efficacy and safety of these agents in delirium. Further research is needed with well-designed studies.