The psychopharmacology of agitation: consensus statement of the American association for emergency psychiatry project BETA psychopharmacology workgroup.

To the Editor:

We were excited to read the article by Michael Wilson et al1 in the March 2012 issue of the Western Journal of Emergency Medicine regarding pharmacologic strategies for the management of agitated patients in the emergency setting. This article highlights several important points including the optimal management of stimulant-induced agitation and the feasibility of and reasons for differentiating acute alcohol intoxication from withdrawal, as optimal pharmacologic interventions for each might vary.

While the authors correctly highlight the importance of preferential use of benzodiazepines to calm patients intoxicated with most recreational drugs, we believe that the use of benzodiazepines as first line treatment for agitation should be extended to include that from acute overdose of other agents.

Because many common medications taken in acute overdose, such as cyclic antidepressants, SSRIs, diphenhydramine and other over-the-counter medications have toxicity profiles that include anticholinergic, proconvulsant, hyperthermic, and cardiotoxic (QTc prolongation) properties, which overlap with antipsychotics, we recommend benzodiazepines as first, second and third line for agitation in these instances to avoid contributing to these potentially life threatening adverse effects. Further, benzodiazepines raise the seizure threshold and promote conditions that precipitate heat dissipation.2,3 If, after liberal use of benzodiazepines, the patient still displays agitation necessitating further pharmacologic intervention, we then use antipsychotics with caution. We found the reported maximum daily dose of lorazepam in the Table1 to be dangerously low.

We were glad to see the emphasis on patient and staff safety, given the increasing awareness of the excited delirium syndrome, thought to be due to a multifactorial interaction of delirium and agitation often secondary to stimulant intoxication, leading to hyperthermia, profound acidemia and sometimes death.4–7 We regret that the authors left out a discussion of the increasing use of the dissociative agent ketamine for rapid control of dangerous behavior in this subset of patients. Although no controlled trials exist regarding its use in agitated patients, several case reports show rapid, satisfactory results adverse without significant respiratory and cardiovascular effects.5,8 Potential adverse effects of ketamine, although uncommon, include hypertension, emergence phenomena, increased oral secretions and laryngospasm.7,10