Leicester flanker Croft, who has recovered from a serious neck injury, played back-to-back matches for the first time this season when he led the Tigers to victory over Sale on Saturday.
Croft was expected to miss the entire Six Nations, but head coach Stuart Lancaster revealed the 27-year-old is available for selection against the Azzurri.
"Tom has been seen by a specialist, played back-to-back games and played 80 minutes at the weekend and did extremely well," Lancaster said.
"In consultation with the medical teams and (Leicester director of rugby) Richard Cockerill, we've brought him back into the camp. He's available for Italy and Wales."
Farrell has lost his battle with the thigh strain sustained against France, so Toby Flood will start against Italy.
"Owen's still got the quad injury which I want to make sure has settled down completely. It's fair to say that you can read into that that Toby Flood will be starting," Lancaster said.
- Sports & Recreation
- Stuart Lancaster