Efficacy of Intrathecal Oxytocin in Patients With Neuropathic Pain

Rationale: The investigators anticipate that oxytocin will be effective after spinal
injection in humans to acutely relieve chronic neuropathic pain.

Objectives: Determine the effect of intrathecal oxytocin on pain and areas and intensity of
hyperalgesia and allodynia in patients with chronic neuropathic pain.

Interventions: A computer generated randomization will be used to determine the group for
each subject. Subjects will be randomized to receive an intrathecal injection of saline
(placebo) or oxytocin.

Inclusion Criteria:

- Weight < or equal to 240 pounds

- Neuropathic pain for > 6 months: with primary pain area below the umbilicus

Exclusion Criteria:

- Hypersensitivity, allergy, or significant reaction to any ingredient of the study drug
or lidocaine

- Any disease, diagnosis, or condition (medical or surgical) that, in the opinion of the
Principal Investigator, would place the subject at increased risk (active gynecologic
disease in which increased tone would be detrimental e.g., uterine fibroids with
ongoing bleeding), compromise the subject's compliance with study procedures, or
compromise the quality of the data

- Pregnancy

- spinal cord stimulators, chronic intrathecal drug therapy, or oral opioid treatment
for > 3 months at a current dose of > 100 milligram (mg) morphine per day or
equivalent.