A survey of patient tolerance and satisfaction with capsaicin for neuroproliferative vestibulodynia
Authors: Kopits Isabella , Krapf Jill M , Moss Chailee , Mautz Theodora , Holloway Jess , Starsiak Lilliana , Lorenzini Sylvia , Goldstein Andrew T 
Published: March 2024

Abstract

Background
Topical capsaicin has been used to treat vulvodynia but has been poorly studied for use in neuroproliferative provoked vestibulodynia (PVD); capsaicin decreases allodynia by blocking vanilloid receptors (TRPV1) on C-afferent nociceptors, but the therapy causes discomfort to the point of intolerance in some patients.

Aim
The present study evaluated tolerability and efficacy of topical capsaicin to treat neuroproliferative PVD.

Methods
Patients with neuroproliferative PVD prescribed 0.025% capsaicin compounded in VersaBase cream were identified through prescription records. Outcome measures included the Female Sexual Function Index (FSFI), the Female Sexual Distress Scale–Revised, and a 22-question questionnaire assessing patient experience and treatment tolerability.

Outcomes
Among tolerant patients, capsaicin significantly decreased vestibular pain, but tolerance was highly variable.

Results
Twenty-five patients responded to the follow-up questionnaire. The average age at presentation was 30 years (range, 18-52 years). Eighty percent of patients tolerated capsaicin application for the full 20 minutes within a median time of 1 to 2 weeks. Of the 16 patients reporting tolerance to 20-minute application, 12 (60%) experienced improvement in vestibular pain. On an 11-point numeric rating scale, the mean pain score was 8.96 and the median score was 10 with first application. Among all participants, 16 (64%) had reduction in pain during treatment. Fifty-six percent of patients would recommend capsaicin as a treatment for vulvar pain. Qualitative content analysis focused on categories of efficacy, value, and feasibility, which indicated that those able to tolerate the treatment experienced improvement while using the medication. The mean Female Sexual Distress Scale–Revised score was 35.96 at baseline compared with 25.09 at follow-up (P &lt; .0001). On a numeric rating scale, the mean self-reported vulvar pain score was 8.2 at baseline compared with 5.35 when using capsaicin consistently (P &lt; .0001). The mean FSFI pain domain score was 2.45 at baseline compared with 0.98 at follow-up (P = .005). While not statistically significant, the mean total FSFI score was 15.44 at baseline compared with 17.84 at follow-up (P = .3730).

Clinical Implications
Capsaicin is helpful for some patients with PVD, but thorough counseling is important because of highly variable tolerance.

Strengths and Limitations
Strengths include examination of a poorly studied therapy and inclusion of narrative responses from patients to inform counseling. Limitations include small sample size, retrospective design, and low survey response rate.

Conclusion
Patients should be appropriately selected and thoroughly counseled given high levels of intolerance, but capsaicin therapy may be considered for patients with neuroproliferative PVD who have failed conservative treatments and wish to avoid surgery.