The Argentine missed last Saturday's 3-3 home draw with Sunderland which helped Manchester United stretch their lead over their local rivals to five points with seven games left.
City boss Roberto Mancini labelled top scorer Aguero's injury "stupid" last week and refused to go into details but it emerged the forward had suffered boils after using a spray on an ankle problem.
Aguero has not given up hope of mega-rich City overhauling champions United.
"Why wait until next season if there is still a possibility we can win it now?" he said.
"We all want to make it and though it won't be easy, we believe we can win the Premier League this season.
"Winning titles is about never giving up and we will never give up. I want to win it this season and then many more with City after that."