comparison of intramuscular olanzapine and ketamine efficacy as first medication for fast sedation of patients with agitation and aggressive behavior. Five hundred patients with agitation caused by psychiatric disorder were randomly assigned under double-blind conditions to receive olanzapine or ketiapine. The Overt Agitation Severity Scale, Overt Aggression Scale and Ramsay Sedation Scale will be applied within 12 hours after the first dosage.