Taken from an E I Lilly press release

Data published in the August issue of the Journal of Clinical Psychopharmacology suggest that an intramuscular formulation of the atypical antipsychotic Zyprexa(R) (olanzapine, Lilly) rapidly reduces acute agitation in patients with bipolar mania. At the same time, Zyprexa IntraMuscular was associated with a low risk of developing movement disorders known as extrapyramidal symptoms (EPS).

Agitation is a well-recognized behavioral syndrome with a range of symptoms, including hostility, extreme excitement, poor impulse control, tension and uncooperativeness. Patients experiencing agitation in its severe forms are usually in an emergency situation and require immediate treatment to alleviate personal distress and to prevent harm to themselves and others.

To date, in the U.S., there are no drugs, either in an oral or intramuscular formulation, specifically approved by the Food and Drug Administration for the treatment of acute agitation in patients with bipolar mania. In the absence of approved therapy, physicians routinely use older typical antipsychotics and benzodiazepines.