Capsaicin 8 % as a cutaneous patch (Qutenza™): analgesic effect on patients with peripheral neuropathic pain

Evaluation of the analgesic effect after a single application of the capsaicin 8 % cutaneous patch (Qutenza (TM)) in 37 patients suffering from painful, distal symmetric polyneuropathy (PNP) for an average of 5 years. Patients ranged from 40 to 78 years of age and 22 subjects were HIV-positive. Patients were observed 4 weeks prior to 12 weeks post administration. An evaluation of the therapeutic effect of capsaicin 8 % as a dermal patch in terms of pain reduction, change of sleeping behavior and social activities was performed and statistical analysis of data was conducted using non-parametric methods. Patients were selected according to clinical criteria. Numerical rating scale (NRS 0-10) was used to inquire pain intensity and a pain score was calculated using the painDETECT(A (c)) questionnaire Freynhagen R (Curr Med Res Opin 22:1911-1920, [2006]). A significant reduction of pain was achieved for up to 12 weeks, with a maximum after 2-4 weeks post administration. After patient education and before application of capsaicin patch, a significant reduction of three levels on the NRS was observed. Symptoms of painful PNP decreased over the period of investigation and 8 patients reported a reduction of systemic pain medication. In patients with an HIV infection, a significant extension of sleep was achieved for 2, 4 and 8 weeks after application. Thus, the application of the capsaicin 8 % patch resulted in a significant relief of neuropathic pain, a prolongation of sleep, a reduction of oral pain medication and a resumption of social activities.