Intraperitoneal AM251 to younger rats attenuates mechanical allodynia. After hind paw burn, mechanical allodynia was observed as early as day 1 after burn and persisted even at day 14 on the untreated ipsilateral (IPSI) compared with contralateral (Contra) side of burn. The administration of AM251 (1 or 0.1 mg/kg daily) was started immediately postburn and continued up to day 7. The dose of 1.0 mg/kg of AM251 attenuated the allodynia at 3, 5, 7, and 14 days. The administration of 0.1 mg/kg AM251 showed no beneficial effects on mechanical alloydynia.