Mick McCarthy has included Troy Parrott and Lee O'Connor in his squad for this month's games against New Zealand and Denmark.
Parrott and O'Connor make the move up from Stephen Kenny's under-21 squad.
McCarthy has welcomed David McGoldrick back from injury while Robbie Brady and Ciaran Clark also return.
"Robbie was left out last month simply because he had only played three minutes in the Premier League all season when I named the squad,” McCarthy told FAI.ie.
“He is back involved with the Burnley first team now and getting game time and his involvement is a real boost to us ahead of the match against Denmark because of the quality he brings to the team.
“I will give Robbie time against New Zealand to get ready for Denmark. He is one of the players in the squad who will really benefit from the New Zealand game before we play the Danes.
“Ciaran is in the same boat. He had to get back with Newcastle before he could back with us but he is playing well for them now and I was impressed with him against West Ham last Saturday.
“David’s return is the big bonus for all of us. Everyone knows how well he has done for us in the European Championship games he has played this year and he has been brilliant for his club in recent weeks.”
Crystal Palace midfielder James McCarthy has asked not to be included for "personal reasons".
Republic of Ireland squad to play New Zealand and Denmark:
Goalkeepers: Darren Randolph (Middlesbrough), Kieran O’Hara (Burton Albion, on loan from Manchester United), Mark Travers (AFC Bournemouth).
Defenders: Matt Doherty (Wolverhampton Wanderers), Shane Duffy (Brighton and Hove Albion), Kevin Long (Burnley), John Egan (Sheffield United), Ciaran Clark (Newcastle United), Enda Stevens (Aston Villa), Derrick Williams (Blackburn Rovers), Lee O'Connor (Celtic).
Midfielders: Alan Browne (Preston North End), Josh Cullen (Charlton Athletic, on loan from West Ham United), Jeff Hendrick (Burnley), Callum O’Dowda (Bristol City), Glenn Whelan (Heart of Midlothian), Conor Hourihane (Aston Villa), James McClean (Stoke City), Jack Byrne (Shamrock Rovers), Robbie Brady (Burnley)
Forwards: Callum Robinson (Sheffield United), Troy Parrott (Tottenham Hotspur), Aaron Connolly (Brighton and Hove Albion), David McGoldrick (Sheffield United), James Collins (Luton Town), Scott Hogan (Stoke City, on loan from Aston Villa), Sean Maguire (Preston North End), Alan Judge (Ipswich Town)