Although many different techniques for opiate detoxification have been employed, there is a continuing search for more effective approaches to reduce the duration and discomfort associated with opioid dependence. It has been shown that very low doses of naltrexone administered in the presence of opiates has analgesic and dependency reducing properties.The purpose of this study is to investigate the effects of very low doses of naltrexone in treating opioid dependent individuals, administered during methadone-tapering, opiate detoxification. In addition, this study will compare the effectiveness of two different dose regimens of naltrexone.

Participants in this double-blind study will be recruited among opioid dependent individuals receiving the standard pharmacological (drug?) protocol to control discomfort during a methadone tapering treatment in a 6 day inpatient detoxification program. Participiants will be randomly assigned to one of three groups. Two of the groups will be given naltrexone; group 1 will receive 0.125 mg each day, while group 2 will receive 0.250 mg each day. Group 3 will receive a placebo. Participants will be evaluated upon enrollment for the severity of their addiction to opiate and then daily for signs of withdrawl and salivary cortisol. In addition, participants will return for an evaluation and completion of a urine test for drugs of abuse at Day 1 following discharge. Daily evaluations will take 15 minutes to complete.

In addition, participants will participate in a telephone interview of about 20 minutes, at Day 7 following discharge. During the phone interview, participants will schedule an appointment to provide a final urine specimen for the detection of drugs of abuse.

Inclusion Criteria:

• Current DSM-IV diagnosis of opiate dependence
• Reads and understands English

Exclusion Criteria:

• Serious medical disorders (e.g., uncontrolled hypertension, acute or chronic active hepatitis, kidney failure, uncontrolled diabetes)
• Psychiatric conditions that require intensive services (e.g., depression with suicidal ideation, psychosis)
• Mental retardation or other disorder that might limit ability to give informed consent
• Pregnant