Scottish police said they had attended a "gathering at a property" in Glasgow in the early hours of Sunday and had issued fines to 10 people.
The Scottish Premiership leaders issued a statement saying they were aware of an alleged incident and had launched an internal investigation.
Speaking to Rangers TV, Gerrard named the five players who had broken the rules.
He said the players -- Bongani Zungu, Nathan Patterson, Calvin Bassey, Dapo Mebude and Brian Kinnear -- would be fined and were currently isolating in line with Covid-19 protocols.
Gerrard, whose team travel to face Antwerp in the first leg of their last-32 tie in the Europa League on Thursday, said he felt "personally let down" but wanted to focus on upcoming matches.