Phase I Open-label Study of Low-dose Ketamine Infusion Treatment in Levodopa-Induced Dyskinesia in Parkinson's Disease

Inclusion Criteria: * Patients diagnosed with Parkinson's Disease as defined by the UK Parkinson's Disease Society Brain Bank Criteria * Be male or female between ages 30-85 * Be on at least two years of treatment of levodopa of at least 400 mg or 4mg/kg daily * Have levodopa induced dyskinesia for at least 2 hours per day * Have been on stable doses of all anti-Parkinson's medications for 30 days and be willing to remain on the same doses throughout the course of the study * The subject/caregiver must demonstrate ability to complete an accurate home diary based on training and evaluation (visit 2) * Female subjects not of childbearing potential * infertile due to surgical sterilization (hysterectomy, bilateral oophorectomy, or tubal ligation), congenital anomaly such as Mullerian agenesis; or * post-menopausal - defined as either * A woman at least 40 years of age with an intact uterus, not on hormone therapy, who has had at least 1 year of spontaneous amenorrhea with a follicle-stimulating hormone level \>40 mIU/mL * A woman 55 or older not on hormone therapy, who has had at least 6 months of spontaneous amenorrhea * A woman at least 55 years of age with a diagnosis of menopause prior to start of hormone replacement therapy. * Male subjects, regardless of their fertility status, with nonpregnant women of childbearing potential (WOCBP) partners must agree to either remain abstinent (if this is their preferred and usual lifestyle) or use a highly effective …