I read with concern the letter Steven Lippmann, MD, wrote (“Treating delirium,” Comments and Controversies, Current Psychiatry, July 2011, p. 53) in response to “Atypical antipsychotics for delirium: A reasonable alternative to haloperidol?” (Current Psychiatry, January 2011, p. 37-46). Although the original article acknowledged that haloperidol has been the “gold standard” in treating agitation during delirium, the authors wrote a review of evidence-based literature, summarizing the emerging literature on the use of other antipsychotics. I agree with Dr. Lippmann that diagnosing and treating the underlying cause of delirium should be the primary focus, but I strongly disagree that benzodiazepines are safer than antipsychotics in managing behavioral aspects of delirium.
The January 2011 article gives a good summary of the literature on using antipsychotics in delirium. I would like to focus on Dr. Lippmann’s assertion that benzodiazepines are safer than antipsychotics. No study has found evidence for benzodiazepines’ effectiveness in non-alcohol–related delirium.1 However, a number of studies have found benzodiazepines are an independent risk factor for delirium.
A randomized controlled trial comparing a benzodiazepine (lorazepam) with antipsychotics (haloperidol, chlorpromazine) to treat patients with delirium had to be interrupted prematurely.2 This study found improvement in delirium symptoms (measured by the Delirium Rating Scale) with both haloperidol and chlorpromazine. The researchers decided to discontinue the lorazepam treatment arm because of unacceptable adverse effects among lorazepam-treated participants, including excessive sedation, ataxia, disinhibition, and worsened confusion.
A study of surgical patients found a significant association between delirium and postoperative exposure to benzodiazepines.3 A study of delirium risk factors in an intensive care unit found lorazepam to be a consistent and significant predictor of delirium.4 Two other studies have found benzodiazepines can cause or worsen delirium.5,6 In conclusion, there is no evidence for use of benzodiazepines to manage behavioral symptoms in delirium. Benzodiazepines alone are not safer than antipsychotics and are not indicated for treating non-alcohol–related delirium.
Rashi Aggarwal, MD
Assistant Professor
Department of Psychiatry
New Jersey Medical School, UMDNJ
Newark, NJ