A Comparison of Topical Local Anaesthesia and Cooling to Reduce the Burning Pain During Capsaicin 8% Patch Application

According to literature, one of the most common adverse events of capsaicin 8% patch is a burning pain and a reversible erythema at the application site. In general it is recommended to apply a topical anesthetic one hour before capsaicin 8% patch application, or to treat the pain with cooling, NSAIDs or even opioids. Nevertheless, there is still only limited data available on the effects and side-effects. In this study it shall be tested if cooling the skin down for about 5-10 Celsius, immediately before Qutenza is applied, and continuing the cooling during the whole application time, results in a reliable prevention of the burning pain compared to pretreatment with topical anesthesia applied one hour in advance. This would lead to the assumption that the application pain is predominantly caused by a decrease of the threshold for heat pain beyond skin temperature and can therefore be prevented by a lowering of the skin temperature.

By ascertaining pain 24 hours after capsaicin 8% patch application and epidermal nerve fiber density (ENFD) 1 week after capsaicin 8% patch application it shall be proved if the different pretreatment methods do not change the secondary effects of capsaicin application.

If results turn out to be positive, it would be a massive relief with regard to time management and rescue medication.