The Welsh region’s forward was shown the red card in Limerick on February 29 by referee Mike Adamson and was cited under law 9.12.
At a disciplinary hearing handled by Rory Bannerman (Scotland), it was accepted that Lousi’s actions warranted a red card for foul play.
The incident was deemed a top-end offence, which carries a ten-week suspension.
Lousi’s previous clean disciplinary record, acceptance of his actions and remorse shown, however, warranted the application of 50 per cent mitigation which brought his ban to five weeks. It leaves him free to resume playing on April 5.
Meanwhile, Connacht’s Peter Robb had his red card in the recent win over Southern Kings in Port Elizabeth rescinded.
Referee Cwengile Jadezweni had deemed the player had committed an act of foul play in the 16th minute when making contact with Howard Mnisi.
However, the decision was not upheld by Roddy MacLeod at a disciplinary hearing, the judicial officer deciding that an act of foul play which warranted a red card had not occurred.