Memantine and Naltrexone Treatment for Opioid Dependence

Inclusion: * Adult, aged 18-60. * Meets DSM-IV criteria for current opiate dependence disorder of at least six months duration, supported by a positive urine for opiates and a positive naloxone challenge test if the diagnosis is unclear. * Able to give informed consent. Exclusion: * Pregnancy or breastfeeding * Failure in a sexually active woman to use adequate contraceptive methods * Active medical illness that might make participation hazardous, such as untreated hypertension, acute hepatitis with SGOT or SGPT levels \> 2 times normal, unstable diabetes, or chronic organic mental disorder (e.g., AIDS dementia) * Active psychiatric disorder that might interfere with participation or make participation hazardous, including DSM-IV schizophrenia, bipolar disorder with mania or psychosis, and depressive disorder with suicide risk or 1 or more suicide attempts within the past year. * History of allergic reaction to buprenorphine, naloxone, memantine, naltrexone, clonidine, or clonazepam * Currently prescribed or regularly taking opiates for chronic pain or medical illness * Current participation in another intensive psychotherapy or substance abuse treatment program or currently prescribed psychotropic medications * Current participation in a methadone maintenance treatment program and/or regular use of illicit methadone ( \> 30 mg per week) * History of accidental drug overdose in the last 3 years or any other significant history of overdose following detoxification, defined as an episode of opioid-induced unconsciousness or incapacitation, whether or not medical treatment was sought or received