The former Bath and Australia rugby lock Justin Harrison has been suspended for eight months after admitting three charges, including taking illegal drugs.
The 35-year-old, who abruptly retired at the end of the last English season, was found guilty of "actions prejudicial to the interests of the game".
Harrison also admitted shouting "class A, it's OK, everyone's doing it" in the vicinity of Bath academy players.
Harrison also pleaded guilty to missing a club drugs test.
Harrison avoided an automatic two-year ban under World Anti-Doping Agency rules because the incident happened out of competition and instead has been punished under RFU charges.
The issue stemmed from an end-of-season party in London in May when Bath players clashed with players from Harlequins.
Harrison's former Bath team-mates Michael Lipman, Alex Crockett and Andrew Higgins have also been charged with conduct prejudicial to the interests of the game.
The trio resigned from the club after allegedly refusing to under drug testing.
In February, Bath and England prop Matt Stevens was given a two-year ban after testing positive for cocaine.
