The 28-year-old has been drafted in as a replacement for Preston's Keith Treacy, who has been withdrawn because of a knee injury.
Fahey was originally omitted from Giovanni Trapattoni's 22-man squad announced on Wednesday, having been selected in the Italian's provisional 29-man group in Dublin a fortnight ago.
Recalled: Keith Fahey has been drafted in as a replacement for Keith Treacy
He was dropped in favour of Wigan's James McCarthy, who has impressed since returning from a lengthy injury lay-off.
However an injury to Treacy means Fahey is now back in the squad to face Wales at Dublin's Aviva Stadium on Tuesday, February 8.
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