The Italian is concerned that the 23-year-old is struggling to manage his life both on and off of the pitch.
The 23-year-old signed for the Rossoneri in January after a troubled end to his time with Manchester City, in which he endured a running dispute with coach Roberto Mancini.
Balotelli looked to have turned over a new leaf as he scored 12 goals between January and the end of last season, but his sending off in Milan's 2-1 defeat to Napoli resulted in a three-match ban following an altercation with the referee in the aftermath of the game.
"Balotelli is a media magnet as well as a great player, and so he has to try and manage his life as best he can," Allegri said. "He’s 23 years old, and he has to understand quickly that he’s not just another 23-year-old and certain sacrifices have to made, just as when he’s in training.
"It’s not possible to prohibit Twitter and the club has no big problems with these things. But there have to be rules that are followed by everyone."
Balotelli was still called up to the national side by coach Cesare Prandelli for the 2-2 draw with Armenia on Tuesday, despite his usual insistence on refusing to select players who are absent for their clubs through injury and suspension.
However, Balotelli's appearance in the Azzurri's final World Cup qualifier looks to have come at a cost after he pulled out of training with an injury ahead of Saturday's clash with Udinese.
"He pulled out of training yesterday because of a pain in his thigh. We have a lot of faith in the national side and if they let him play, they must have him ready," Allegri said.
Milan has won just two of its opening seven Serie A games and sits in 12th position ahead of the weekend.