Oxytocin Treatment of Schizophrenia

Inclusion Criteria: * Meeting DSM-IV criteria for paranoid or undifferentiated schizophrenia for at least 1 year. * Scoring \> or equal to 4 on the suspiciousness/persecution (paranoia) subscale of the Positive and Negative Symptoms Scale (PANSS), a full PANSS score \> or equal to 60: stability of symptom severity and on the same medication(s) and dose(s) for at least 1 month; low to moderate depressive symptoms. Exclusion Criteria: * Low literacy as indicated by an inability to read and understand the consent form. * Dependence on substances other than tobacco or caffeine. * Positive urine drug screen for illegal substances or drugs that have not been prescribed. * Debilitating medical conditions (including AIDS; HIV infection alone will not be grounds for exclusion). * Major surgery or trauma in the past year will be grounds for exclusion although subjects determined to be recovered and stable may be included at the discretion of the PI. * Pregnancy, breast-feeding. * Having given birth in the past 6 months or breast-feeding in the past 3 months. * Individuals judged unable to learn self-administration of intranasal treatments and/or not sufficiently reliable to do so will be excluded. * Abnormalities found during medical evaluation will be grounds for exclusion although subjects with laboratory measures barely outside the normal range may be included at the discretion of the Principal Investigator.