Solomona, 24, contested the charge but was found guilty by the RFU's independent panel.
"The panel found that the player used language that was verbally abusive on more than one occasion in quick succession," panel chair Samantha Hillas said in a statement.
"The comments were offensive and have no place on the rugby field. However, the Panel accepted that they were said in the heat of the moment rather than premeditated.
"For these reasons, the panel deemed it was a low end entry point which carries a six week suspension as a starting point. The player did not accept the charge but all other mitigating features were present. The panel therefore reduced the sanction to four weeks."
Solomona is banned until May 8, which means he will not play again this season unless Sale reach the Premiership playoffs.
France centre Mathieu Bastareaud was suspended for three weeks in January for making homophobic comments in a Champions Cup match for Toulon, and went on to miss the start of the Six Nations campaign.
The sport's other major incident involving homophobic slur saw New South Wales Waratahs forward Jacques Potgieter handed a fine of A$20,000 (£10,970) for calling ACT Brumbies players "faggots" in a Super Rugby match in March 2015.
(Reporting by Hardik Vyas in Bengaluru; editing by Sudipto Ganguly)
