Sexton was a doubt for the match in Paris against France that was eventually postponed with Ronan O'Gara on stand-by to take the No.10 shirt.
But while the Leinster stand-off believes he would have started against Les Bleus, he is eager to get the frustration of their defeat against Wales at the Aviva Stadium out of his system.
"I was fit to play over in Paris," he told a news conference. "I just had a slight niggle a couple of days beforehand but it was fine.
"I've recovered enough. It was a weird week. We came in for a one-day camp last week and the lads are excited about getting back playing now.
"We've had a bit of a break since the Wales game and to have that hanging over you for an extra week is not the nicest feeling.
"We worked hard in training and tried to simulate a game as much as we could last week.
"The more you play, the better you play but at the same time being fresh is key as well. I think you can take the positives out of both."
Despite their opening two defeats, Sexton says Ireland will not be underestimating the Azzurri and has full respect for his likely opposite number Kris Burton.
"I thought Burton was going okay," he said. "They obviously took him off against England it probably cost them.
"We played against Burton in Treviso and he's a good player and a threat. We'll have to keep our discipline, keep him out of drop-goal range and put a lot of pressure on him when he does go for those drop goals.
"Their strength is up front. They might be missing Castrogiovanni, which is a big loss for any side, but they've got strength in depth in that area, and they've got some backs playing in the Top 14."