Capsaicin For Neuropathic Pain: An Update

Today's post from informahealthcare.com (see link below) is a short summary of the findings of a German research study into the effectiveness of high-strength capsaicin patches in reducing neuropathic pain (Qutenza is the most commonly used). Capsaicin cream and patches have sort of fallen off the radar in the last two years but remain an alternative treatment for neuropathic pain. Their reduced popularity may well be due to the difficulty of application and the care needed to avoid burning. The base component capsaicin comes from chili peppers and is extremely powerful, especially in the concentration used on the patches. You really do need expert guidance as to how to apply them and what to do if the negative symptoms are too strong. That said, studies consistently show that capsaicin high strength patches do work in reducing nerve pain. If you've not thought about them, it may be worth discussing the option with your doctor.

High concentration capsaicin for treatment of peripheral neuropathic pain:

...effect on somatosensory symptoms and identification of treatment responders
April 2014, Vol. 30, No. 4 , Pages 565-574 (doi:10.1185/03007995.2013.869491)

Johanna Höpera, * Stephanie Helferta, * Marie-Luise S. Heskampb, Christian G. Maihöfnerc, Ralf Barona
aDivision of Neurological Pain Research and Therapy, Department of Neurology, University Hospital Schleswig-Holstein,
Kiel, Germany
bMedical Department, Astellas Pharma GmbH,
Munich, Germany
cDepartment of Neurology, Fürth Hospital,
Fürth, Germany
Address for correspondence:
Prof. Dr. med. Ralf Baron, Division of Neurological Pain Research and Therapy, Department of Neurology, University Hospital Schleswig-Holstein,
Campus Kiel, Arnold-Heller-Str. 3, Haus 41, 24105 Kiel, Germany. Tel: +49 431 597 8504; Fax: +49 431 597 8530; r.baron@neurologie.uni-kiel.de

*These two authors contributed equally to the paper.

Background:
Pain is usually assessed by spontaneous pain ratings. Time-dependent (brief attacks) or evoked (allodynia) phenomena, common in neuropathic pain, are not captured. To evaluate the overall effectiveness of a treatment, improvement of all sensory symptoms should be measured. Since the pattern of sensory abnormalities might hint at the underlying mechanisms of pain, this baseline information may aid in predicting the treatment effect. Data on sensory neuropathic abnormalities (painDETECT questionnaire) were analyzed aiming to (1) evaluate the frequency of neuropathic symptoms in different peripheral neuropathic pain syndromes, (2) assess the effect of capsaicin 8% patch on neuropathic symptoms and (3) identify treatment responders based on baseline values.

Methods:
Data analysis of a prospective 12 week non-interventional trial in peripheral neuropathic pain treated with capsaicin 8% cutaneous patch. Average pain intensity during the past 24 hours, pain descriptors and qualities of neuropathic pain were assessed to characterize the patients’ sensory symptoms at baseline and to document changes.

Results:
(1) Characteristic symptoms of neuropathic pain were present in all peripheral neuropathic pain syndromes, but frequencies varied in the individual syndromes. (2) Topical capsaicin 8% treatment significantly reduced the overall pain intensity and resulted in a reduction of sensory abnormalities. (3) Short disease duration predicted a better treatment effect. High painDETECT scores, the presence of burning and pressure-evoked pain were weakly associated with treatment response.

Conclusions:
Topical capsaicin 8% treatment effectively reduced sensory abnormalities in peripheral neuropathic pain. The association of sensory symptoms and treatment response aids in understanding the mechanism of action of high concentration capsaicin. It is, however, not possible to use sensory symptom patterns to predict treatment response to capsaicin on an individual level.

Limitations:
Completion of painDETECT was optional and therefore data was not available for all patients. Further studies for confirmation of these results are needed.

http://informahealthcare.com/doi/abs/10.1185/03007995.2013.869491