Patients who had repeated use of intramuscular (IM) antipsychotics experienced a significantly longer length of stay (LOS) in the emergency department (ED) vs. non-repeat users of IM antipsychotics, according to a new study published in Journal of Psychiatric Practice.

To avoid violence in the psychiatric ED, timely recognition and treatment of agitated patients is critical. Although antipsychotics have shown efficacy in managing acute agitation, not much is known about how the initial antipsychotic used affects time to repeat use and LOS in the ED. 

To understand the impact, pharmacists from the University of Southern California, Los Angeles, CA, conducted a chart review (n=383) to identify cases involving patients who were given an antipsychotic for agitation in the psychiatric ED between July 1 and August 31, 2014. The agents compared were IM haloperidol, other IM antipsychotics, and oral 2nd-generation antipsychotics. 

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Of the total cases, almost one-third (31%) required repeat medications. For IM haloperidol, mean time to repeat use was 20.1±18.4 hours, which did not significantly differ when compared to groups receiving other IM antipsychotics or oral 2nd-generation antipsychotics (P=0.35) (range 14 to 20 hours).

IM antipsychotics were linked to longer LOS (IM haloperidol: mean LOS of 29.7±28.7 hours, other IM antipsychotics: mean LOS 30.3±36.9 hours) compared to oral 2nd-generation antipsychotics (mean LOS of 22.6±28.0 hours). Study authors noted significant differences in LOS between repeat vs. non-repeat users of IM haloperidol and other IM antipsychotics but not for those who received oral 2nd-generation antipsychotics.

While repeat users of IM antipsychotics showed a significantly longer LOS in the ED vs. non-repeat users of IM antipsychotics, patients who were initially given oral 2nd-generation antipsychotics did not have longer LOS even if a repeat dose was administered, the study authors concluded. 

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