Objective: Social Cognition and Emotional Intelligence have been shown to be deficient in patients with schizophrenia and these are not remediated by antipsychotic medications or psychosocial interventions. Social cognition is associated with functional outcome, an important step in striving for recovery in this population. The hormone and neurotransmitter, oxytocin, which has been associated with social bonding and trust has been shown to improve measures of some aspects of social cognition in humans. The study will assess the effect of acute administration of intranasal oxytocin on measures of social cognition and functioning as well as on emotional intelligence and symptoms.

Study population: The study population will include patients with a DSM-IV diagnosis of schizophrenia or schizoaffective disorder who have been on a stable medication regimen for 6 weeks. We will enroll a total of 30 subjects (N=15 placebo and N=15 oxytocin groups).

Experimental design and methods: After a one week lead in phase, participants will undergo 3 weeks of oxytocin (20 IU BID) or placebo administration (double blind) in addition to their existing medication regimen. Outcome measures will be administered during the lead in phase, and at the end of the study drug administration phase (under the acute effect of OT). The primary outcome measure will be the Mayer-Salovey-Caruso Emotional Intelligence Test (MSCEIT) and the Maryland Assessment of Social Competence (MASC). Secondary measures include rating from the domains of social cognition (emotion perception, attributional style, theory of mind and social perception), symptom rating and measures of social anxiety and quality of life. Side effects and symptoms will be measured weekly.

Inclusion criteria:

All participants must:

1. Be between age 18 and 55.
2. Meet DSM-IV criteria for Schizophrenia or Schizoaffective Disorder.
3. Treated with a stabilized antipsychotic regimen (i.e., have had no change in antipsychotic medication in the previous six weeks and no change in dose for the past 30 days).

Exclusion criteria:

Participants will be excluded if they have evidence of:

1. DSM-IV criteria for substance dependence in the last 6 months or DSM-IV criteria for abuse in the past 30 days.

2. Cognitive impairment severe enough to preclude informed consent or valid responses on questionnaires. This is defined an as a score of less than 10 on the Evaluation to Sign Consent (ESC) and judged by the treating clinician.

3. Medical illness that in the view of the investigators would compromise participation in research.

4. History of polydipsia and/or hyponatremia

5. Clinically significant endocrine disorders, as judged by the PI. Abnormalities in prolactin levels and thyroid function tests associated with the use of dopamine antagonist medications will not be exclusionary.

6. Pregnancy, planning to become pregnant, or breastfeeding. In addition, women of childbearing age are required to use an effective form of birth control for the duration of the study. Effective forms of birth control include:

   • hormonal contraceptives (birth control pills, injectable hormones, vaginal ring hormones),
   • surgical sterility (tubal ligation or hysterectomy)
   • IUD
   • Diaphragm with spermicide
   • Condom with spermicide
   • Abstinence

7. Use of any drugs (prostaglandins, vasoconstricting agents or anesthetic medications, for example) that may interact with oxytocin. Justification: Avoidance of adverse interaction with oxytocin. Assessment tool(s): Clinical interview and toxicology screen

8. History of hypersensitivity to oxytocin or vehicle, i.e. propyl parahydroxybenzoate, methyl parahydroxybenzoate, chlorobutanol hemihydrate. Assessment tool: clinical interview

9. Presence of or history of clinically significant allergic rhinitis as assessed by the PI, M.D., or Nurse. Justification: Inflammation of nasal mucosa could interfere with mucosal absorption of intranasally administered OT. Current rhinitis from an upper respiratory infection should be resolved prior to enrollment in study.

Baseline participants are participants that were randomized to one of the two treatment groups.