The Leinster flanker is struggling with a knee injury.
Leinster’s Will Connors will miss the rest of the season.
The flanker sustained a knee injury in last month’s defeat to Cardiff.
Connors had only returned to action following eight months out in November.
Meanwhile, Leinster duo James Lowe and Eadestown's Jimmy O’Brien have joined the Ireland squad ahead of Sunday’s Six Nations meeting with Italy.
Lowe had missed the first two games with a hamstring injury.
While O’Brien could win his first cap against the Azzurri.

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