Drug treatment of delirium: Past, present and future

Richard S. Bourne, Sheffield Teaching Hospitals, Sheffield, UK
Tayyeb Tahir, Aga Khan University
Mark Borthwick, Oxford Radcliffe Hospitals, Oxford, UK
Elizabeth L. Sampson, Enfield and Haringey Mental Health Trust, London, UK

This work was published before the author joined Aga Khan University.

Abstract

Objective

The aim of this review was to summarize and critically evaluate the current literature regarding the safety and efficacy of drug therapy in delirium. We also identified recent research developments and highlighted some ongoing clinical trials to explore future directions in drug treatment and prevention of delirium.

Methods

We conducted a literature search of Medline, Embase, PsychInfo, and Cochrane Review databases, which included both prospective and retrospective clinical trials and case studies on delirium and drug therapy in adult patients up to March 2008. Abstracts from recent topical conferences were also reviewed. Ongoing delirium drug studies were identified via the WHO International Clinical Trials Registry Platform Search Portal, accessed March 12, 2008.

Results

The evidence base for effective drug treatment of delirium is restricted by limitations in many of the studies conducted to date. However, there has been an increase in the quantity and quality of delirium drug studies in recent years; preliminary reports and ongoing studies add to this trend. Although efficacy rates between typical and atypical antipsychotic agents are similar, the latter are associated with fewer extrapyramidal side effects. Prophylactic interventions with antipsychotic and cholinesterase inhibitors in high-risk patients provide an opportunity to improve postoperative patient care. Alternative techniques and medication opportunities could be explored in attempts to minimize drug induced delirium potential.

Conclusions

Appropriate drug therapy should be considered part of systematic approaches to delirium treatment and prevention. There is a need for well-designed randomized, double-blind placebo-controlled trials investigating the drug management of various aspects of delirium, including delineating treatment by delirium subtype, dose ranging studies, and optimal duration of therapy.