Having helped Western Province win the Currie Cup Final on Saturday, Stormers’ back row Carr is due to join Wasps this week to provide extra depth following back row injuries at the club.
Carr, who can play flanker or number 8, has won five caps for the Springboks.
Speaking about the short-term signing, Wasps’ Director of Rugby Dai Young said: “We are pleased to be able to bring a player with international experience like Nizaam into the squad to bolster our back row options.
“Having lost Alex Rieder to a dislocated shoulder and with Ashley Johnson no longer being a back row option due to injuries at hooker, we have become pretty threadbare in that area.
“Nizaam has a strong reputation for his defence, athleticism and linking play and I’m sure he will prove himself a valuable addition to the squad even on a short-term basis. We look forward to welcoming him to the club.”