An open-label study was performed to investigate the clinical efficacy and tolerability of olanzapine orally disintegrating tablets (Zyprexa Zydis) in ameliorating excitement symptoms in the acute phase of schizophrenia. Fifty-three patients meeting DSM-IV criteria for first-episode schizophrenia and treated with olanzapine monotherapy were evaluated with regard to their clinical improvement, behavioural response to medication, and extrapyramidal side effects using the Positive and Negative Syndrome Scale Excited Component (PANSS-EC), Nursing Assessment of Medication Acceptance (NAMA), and Drug-Induced Extra-Pyramidal Symptoms Scale (DIEPSS), respectively. Scores of PANSS-EC were significantly reduced after 3 days of olanzapine administration. A reduction in NAMA scores was also observed 7 days after administration of olanzapine. The DIEPSS score was unaffected by olanzapine administration. These results suggest that olanzapine orally disintegrating tablets are effective and well-tolerated for treatment excitement in the acute phase of schizophrenic patients. In addition, it is possible that adherence to medications is improved by using olanzapine orally disintegrating tablets.