Arsenal striker Chuba Akpom has moved to Hull City on a season loan, while Dame N'Doye is set for a move to Turkey.
Barnsley have signed goalkeeper Nick Townsend from Birmingham on a short-term youth loan.
The 24-year-old Irishman made 16 appearances for the Tractor Boys earlier this season and will now return to Portman Road. The deal includes a 24-hour recall option.
A former Republic of Ireland U21 international, Henderson played in two Capital One Cup games for West Ham in August but has been consigned to a substitute's role since returning from Ipswich in early January.
Henderson, who is in the Republic of Ireland's senior squad for the friendly against Poland, could be between the sticks for Ipswich's home clash with Middlesbrough on Saturday.