Pilot Study of RR-HNK in OCD

Inclusion Criteria:

* Ages 18-65
* Meet the criteria for OCD diagnosis
* Failed at least 1 prior trial of standard first-line OCD treatment (e.g. SRI/CBT) or or had refused these treatments for individual reasons
* Agree to the following lifestyle modifications: comply with requirements for fasting prior to --the infusion session, not enroll in any other interventional clinical trials during the duration of the study, and commit to medication study procedures.
* Able to provide informed consent

Exclusion Criteria:

* Allergy or hypersensitivity to ketamine
* Any current or past medical/psychiatric condition that makes participation unsafe in the opinion of the investigator or study physician
* Pregnant or nursing, or able to become pregnant and are not practicing an effective means of birth control
* Lifetime history of deep brain stimulation