The 24-year-old made his Ireland debut as a replacement against Argentina last May. He started Munster's first four games in the Magners League this season before Peter Stringer returned from World Cup duty in recent weeks.
Gerry Hurley, who is the only other recognised scrum half in Munster's 38-man Heineken Cup panel, looks set to take O'Leary's place in the province's squad for next Sunday's Heineken Cup clash with Clermont Auvergne at Thomond Park.
Hurley kicked a last-gasp penalty to guide Garryowen to a 19-18 victory over Dolphin in AIB League Division One on Saturday.
Meanwhile, there is encouraging news from the Munster camp regarding prop John Hayes' neck injury. Hayes was forced off in the first half of the Wasps game. However, since then, the injury has not worsened and the Ireland front rower should be fit enough to take part in training on Wednesday.
Speaking after the one-point loss in Coventry, Munster coach Declan Kidney said: "We will give John the 48 hours and assess how he is then. His neck was a bit sore and it wouldn't have been right for him to go back (on after being replaced by Tony Buckley)."
Winger Ian Dowling is also due to train with the Munster squad on Wednesday after recovering from the illness which kept him from taking a place on the replacements bench for the Wasps game.