Opiate dependence is a serious problem, and oxytocin has many properties which make it attractive as a treatment for this type of substance dependence. This experiment will test the effects of oxytocin on a variety of brain-based processes in patients with opiate dependence. The investigators hypothesize that intranasal oxytocin in these conditions will enhance emotional processing and will have beneficial effects on stress responses in opiate-dependent patients.

Inclusion Criteria:

• adult men 18 years or older
• meet DSM-IV criteria for opiate dependence, and no other active substance dependence disorder save nicotine dependence
• clinically stable, and low risk for suicide as determined by principal investigator and screening questionnaire
• abstinent from non-prescribed opiate use for at least two weeks from Baseline 1 and free from opiate withdrawal symptoms. If on agonist therapy, dose must be stable for 2 weeks before study visit.
• must be able to use nasal spray
• negative salivary drug screen, save for opiates

Exclusion Criteria:

• any active medical condition that in the opinion of the investigator will interfere with the objectives of the study
• any active, severe mental illness, neurological disorder, including schizophrenia, autism, Asperger's syndrome
• are unsuitable in any way to participate in this study, in the opinion of the investigator
• hospitalizations due to complications of an Axis 1 disorder for the past 12 months, excluding drug or alcohol rehabilitation
• any clinically significant chronic pain condition, as determined by the principal investigator
• positive salivary drug screen at the time of the visit, for any substance other than opiates or another prescribed medication