The primary aim of this study is to determine the efficacy of milnacipran in reducing pain in women with provoked vestibulodynia (PVD), a centrally mediated pain syndrome similar to fibromyalgia, that is characterized by severe pain in the vestibule (outer vagina). The investigators will also determine whether associated symptoms in PVD, including psychological distress, impairment of sexual function, physical function, and quality of life, are correlated with a reduction in vulvar pain.

This is an 18-week, open-label, flexible-dose "proof of concept" trial where women with a diagnosis of vestibulodynia will be evaluated at baseline for eligibility. Eligible patients will be openly treated with 200 mg/d milnacipran (or the maximum tolerated dose) for a total of 12 weeks. The study design involves 4 phases: screening and washout, baseline assessment, dose escalation, and stable-dose phase (Figure 1). After completing a 2-week washout of prohibited medications, patients will enter a 2-week baseline period, where they will be trained in the use of daily diaries and the tampon test, and baseline safety and efficacy data will be recorded. Patients who continue to meet the eligibility criteria at the end of the baseline period will begin a 6-week period of dose escalation. All patients will be scheduled to receive a total of 12 weeks of stable dose treatment after the 6-week dose-escalation period for a total of 18 weeks of drug exposure.

Inclusion Criteria:

1. women between 18-54 years of age,
2. 'Friedrich's Criteria' must be met (report greater than six continuous months of vulvar symptoms including insertional dyspareunia or pain to touch, demonstrate on physical exam moderate to severe tenderness to light touch, localized to the vulvar vestibule [positive Cotton Swab Test] and demonstration of variable degrees of erythema of the vestibule),
3. an average pain level of "4" or greater on the 10-point tampon test and/or an average pain level of "4" or greater on the sexual intercourse pain scale(0 = no pain at all; 10 = worse pain ever) during the 2-week screening period(see Study Parameters Section), and
4. willing to use two forms of contraception during the study.

Exclusion Criteria:

1. other vulvar conditions, including dermatoses, vulvitis, vulvar papillomatosis, and atrophic vaginitis (presence of a maturation index),
2. previous vestibulectomy,
3. active vaginal infection,
4. neuropathology, including seizure disorder or syncopal episodes,
5. pregnancy or at risk for pregnancy and not using a reliable birth control method for at least 3 months prior to entering the study,
6. breastfeeding,
7. major medical illness including chronic liver disease/hepatic impairment, renal impairment, narrow-angle glaucoma, or uncontrolled hypertension,
8. major psychiatric illness including substance abuse,
9. multiple allergies (greater than three drugs or environmental agents),
10. use of centrally-acting agents, including monoamine oxidase inhibitors, benzodiazepines, opiates, muscle relaxants, and antidepressants within 2 weeks of randomization and during the study, and
11. use of topical lidocaine, within 2 weeks of randomization and during the study, as it has shown to be an effective treatment in some women, while worsening symptoms in others. Subjects will be permitted to take acetaminophen, aspirin, or a nonsteroidal anti-inflammatory drug as rescue medication. They will be provided with a list of allowable escape medications and those which would constitute a protocol deviation.