Objective: Considering supportive evidence on N-acetylcysteine (NAC) effectiveness in neuropathic pain syndromes, we conducted this study to evaluate its effect on women suffering from chronic pelvic pain syndrome (CPPS).
Methods: In a randomized, double-blind study, 106 women with CPPS were assigned to receive NAC+amitriptyline or placebo+amitriptyline treatment. Amitriptyline was administrated at a dose of 25 mg/daily and NAC and placebo at 600 mg twice daily. The effect of treatment was assessed on the National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) and its domain scores, including pain, urinary symptoms, and quality of life impact scores at weeks 4 and 8 after treatment. The global response was also assessed on the 7-point patient-reported global response assessment (GRA) scale at the end of the study.
Results: By week 4, comparative improvements were noticed in the two groups' NIH-CPSI total score and domain scores. From week 4 to week 8, we noted the superior efficacy of NAC+amitriptyline treatment over placebo+amitriptyline in improving the NIH-CPSI total score and its domain scores, as the proportion of patients responding to treatment (the subjects with ≥ 6-point reduction in the total NIH-CPSI score), as well those reporting marked or moderate improvements in their overall symptoms on GRA was significantly more significant in patients receiving NAC+amitriptyline treatment relative to those receiving placebo+amitriptyline treatment.
Conclusion: These findings provided preliminary evidence regarding the possible role of NAC as an adjunct therapy in the management of CPPS in women, which needs to be validated in future studies.
Keywords: Inflammation, oxidative stress, neuropathic pain syndrome, chronic pelvic pain syndrome, N-acetylcysteine, global response assessment.