Charlie Allen and Joe Martin continue to miss out for the Gills.
Midfielder Allen and full-back Martin are both missing with long-term wrist injuries as the Gills aim to spoil Brian Laws' third managerial return to the Iron, who are struggling at the wrong end of the League One table.
Robbie Findley has gone back to Nottingham Forest following the completion of his one-month loan deal at the club.
But Gills duo Adam Birchall and Connor Essam are both back at Priestfield following their stints with Dartford and Luton respectively.
Midfielder Charlie Lee made his welcome return to the bench for last weekend's 1-0 win at AFC Wimbledon after a lengthy recovery from a leg injury.
Striker Deon Burton (knee) missed out at Kingsmeadow but is expected to be back in contention.
Newly-appointed Scunthorpe manager Brian Laws will be without two key loan players.
The tie will be Laws' first match back as Irons boss since he succeeded Alan Knill on Monday and he inherits a side searching for their first win in eight games.
However they do so without top scorer Leon Clarke and David Prutton, who have been refused permission to play in the cup by their parent clubs, Charlton and Sheffield Wednesday respectively.
Midfielder Damien Mozika will make the trip to Kent as he moves closer to a return from a long-term ankle knock.
While winger Andy Barcham is also in contention after recovering from an injury that has kept him sidelined for the previous two matches.