Olanzapine is considered safer than other antipsychotics due to it’s lower risk of extrapyramidal side effects and it’s minimal impact on QTc. When combined with benzodiazepines though, this can increase overall risk of respiratory depression.
Although olanzapine is effective for acute agitation, it does require reconstitution which may delay it’s administration time. This may be problematic for the severely agitated or violent patient.
Ziprasidone tends to have a faster onset of action, reduced extrapyramidal symptoms, and superior efficacy over typical antipsychotics such as haloperidol. However, it does prolong the QTc interval more than any other antipsychotic agents.
For the undifferentiated agitated patient, benzodiazepines (ex. midazolam) are the drugs of choice. For agitation caused by known psychosis, intoxication, or sundowning, agents like ziprasidone are better options.