A Pilot Study on the Efficacy of Oral Low Dose Naltrexone for Vulvodynia

The goal of this observational pilot study is to assess the safety, efficacy, and tolerability of oral low dose naltrexone (LDN) in the treatment of vulvodynia. The aims it will address are: Aim 1:To assess the efficacy of LDN by reviewing patient-reported Global Treatment Improvement scale scores after the 4-week treatment period. Aim 2: To identify the impact on overall and vulvar pain by calculating the difference between average pre- and post-treatment PGIC, NRS, CSI and VPAQ scores. Aim 3: To identify adverse effects that patients may experience during treatment to better understand the safety profile of this medication. Participants will \[describe the main tasks participants will be asked to do, interventions they'll be given and use bullets if it is more than 2 items\] * Attend a baseline clinic visit and complete PGIC, NRS, VPAQ, and CSI questionnaires * Take 4.5 mg LDN once daily for 4 weeks * Discontinue LDN and contact the health care team immediately in the event of adverse effects * Attend a follow up appointment 4 weeks after medication initiation

Inclusion Criteria: * At least 3 months postpartum * Diagnosis of moderate to severe vulvodynia as defined by persistent vulvar pain for at least 3 months duration with an unclear etiology (defined by a minimum pain score at baseline using NRS and VPAQ questionnaires). * Prior therapy may include conservative management options (vulvar care guidelines, vaginal hormone therapy, neuromodulators etc.) Exclusion Criteria: * Pregnancy or breastfeeding. * Positive urine pregnancy test at study entrance, for subjects of childbearing potential * Unwillingness to use contraception during treatment and for one week after last dose if subject is of childbearing potential and sexually active with males. * Known hypersensitivity to naltrexone. * Prior or concurrent use of other systemic or topical treatments for vulvodynia (except topical hormonal therapy) within 3 months of enrollment. * Pelvic treatment with botulinum toxin injection within the last 12 months prior to the baseline visit * Use of opioids in any formulation (including pain medication, cough suppressants, and anti-diarrheal agents) within two weeks prior to study entrance. * Positive toxicology screen for opioids at study entrance. * Active gynecologic malignancy. * Elevated hepatic enzymes on screening laboratory assessment (ALT ≥1.5- fold ULN, AST ≥1.5-fold ULN, alkaline phosphatase ≥1.5-fold ULN, or/or total bilirubin ≥1.5-fold ULN, with the exception of known Gilbert's disease) * Known cirrhosis (compensated or decompensated) * Kidney disease defined as estimated glomerular filtration rate (eGFR) \< 60 ml/minute on screening laboratory assessment using the Cockcroft-Gault Formula. * Any history (past or current) of suicidal ideation or attempt. * Evidence of suicidal ideation on baseline screening using the Columbia Suicide Severity Rating Scale (C-SSRS). * Uncontrolled depression. * Unwillingness to refrain from driving/operating heavy machinery until the effect of the drug on drowsiness/somnolence is determined by the subject.