Ah, the Medicine of Youth

is episode 186 of the Naruto: Shippūden anime.

Synopsis
Story setting of this episode is around Lee's surgery. Naruto, Sakura and Ino are sent in Jofuku Forest to deliver a message to Furofuki. On the way there, they were petrified because an old lady from the village's inn said that the place was haunted. Naruto managed to take a sample of Jofuku flower for Lee's recovery. They also fought a deity representing Gaara, but Naruto managed to defeat him. They arrived at Furofuki's house and completed their mission.