Nasal delivery of lidocaine decreases carrageenan-induced orofacial pain [abstract 1782] Abstract uri icon

abstract

  • Objectives: Intranasal lidocaine has been demonstrated to target the trigeminal nerve and decrease trigeminal neuralgia pain in humans. This study used a novel behavior apparatus to assess the effect of intranasal lidocaine in a rat model of carrageenan-induced orofacial pain. Methods: The TrigeminAir behavior apparatus was used, which is designed to present air pressure on the sensitized, carrageenan-inflamed whisker pad and electronically measure sip rate of a sweetened condensed milk reward. A computer continuously recorded sip rate for six rats simultaneously. Results: Increased doses of carrageenan (0%, 2%, and 4%) resulted in decreased sip rate (p<0.01) in the TrigeminAir from 5 to 12 hours post-carrageenan injection. Intranasal 10% lidocaine reversed (p<0.05) the effects of carrageenan on sip rate compared to intranasal 0% lidocaine. Conclusions: These results along with previously published evidence indicate that intranasal lidocaine is an effective trigeminal nerve block to orofacial structures. TrigeminAir is a novel method of screening for orofacial pain models and treatments in rats, particularly trigeminal neuralgia.

publication date

  • 2011