Dextrorphan for Prolonged Skin Infiltration Anesthesia by Adding Epinephrine in Rats

• DOI: 10.14205/2310-9394.2014.02.02.3
• Publication Date: 2014-12-16T09:22:40Z
• Authors: Yu-Wen Chen; Kuan-Ting Chen; Jhi-Joung Wang

Dextrorphan could be a local anesthetic, while adding epinephrine to the local anesthetics prolonged their duration of action. Here we investigated whether epinephrine as adjuvant could prolong the local anesthetic effect of dextrorphan. The cutaneous analgesic effect of the addition of epinephrine (5 μg/mL) to dextrorphan was assessed in rats following the blockade of cutaneous trunci muscle reflex through subcutaneous injection of drugs. We showed that subcutaneous dextrorphan elicited dose-dependent cutaneous analgesia. Co-administration of epinephrine (5 􀀁g/mL) with dextrorphan at 50% effective dose (ED50) or ED95 had a longer duration than dextrorphan (ED50 or ED95) alone, respectively. This study indicated for the first time that the mixtures of epinephrine with dextrorphan increased the duration as an infiltrative anesthetic.