The Effect of Brief Potent Glutamatergic Modulation on Cocaine Dependence

Inclusion Criteria:

* Active cocaine dependence with at least 8 days of use or at least 4 binges of large amounts (\>$200/occasion) over the past 30 days, and displaying at least one positive utox during screening
* Physically healthy
* No adverse reactions to study medications
* 21-60 years of age
* Capacity to consent and comply with study procedures, including sufficient proficiency in English
* Seeking treatment

Exclusion Criteria:

* Meets DSM IV criteria for current major depression, bipolar disorder, schizophrenia, any psychotic illness, including substance induced psychosis, and current substance-induced mood disorder with HAMD score \> 12.
* Physiological dependence on another substance requiring medical management, such as alcohol, opioids, or benzodiazepines, excluding caffeine, nicotine, and cannabis
* Delirium, Dementia, Amnesia, Cognitive Disorders, or Dissociative disorders
* Current suicide risk or a history of suicide attempt within the past year
* Pregnant or interested in becoming pregnant during the study period
* Heart disease as indicated by history, abnormal ECG, previous cardiac surgery.
* Unstable physical disorders which might make participation hazardous such as end-stage AIDS, hypertension (\>140/90), WBC \< 3.5, active hepatitis or other liver disease with elevated transaminase levels (\< 2-3 X upper limit of normal will be considered acceptable if PT/PTT is normal), renal failure (creatinine \> 2, BUN \>40), or untreated diabetes
* Previous history of ketamine or benzodiazepine misuse or abuse, and a history of an adverse reaction/experience with prior exposure to ketamine or benzodiazepine
* Recent history of significant violence (past 2 years)
* First degree relative with a psychotic disorder (bipolar disorder, schizophrenia, schizoaffective disorder, or psychosis NOS)
* BMI \> 32, or a history of documented obstructive sleep apnea
* On psychotropic or other medications whose effect could be disrupted by participation in the study
* Patients who cannot comply with study procedures during the initial hospitalization phase