The Courier-Mail on Monday reported Jason Singh, said to be a distant cousin of 2003 premiership player Ash McGrath through marriage, made a series of threats on his Facebook page to reveal his claims of illegal practices from 2002 to 2009.
Singh told the newspaper he had been a drug supplier between 2002 and 2009 and named six Lions players from that period whom he claimed were heavy users of speed, ecstasy and marijuana.
He also claimed he was involved in fixing an AFL match involving the Lions in 2003 and had regularly received team information from Lions players before games for the purposes of betting.
The Lions dismissed the claims in a statement released on Monday.
"It is extremely disappointing that the Courier Mail has chosen to publish this story in the absence of any evidence," the statement read.
"These claims from a 'self-confessed drug dealer' are completely unsubstantiated and do not deserve publicity.
"We have no reason to believe the word of a 'self-confessed drug dealer' but if anyone, including the Courier Mail, has any evidence with regards to this, or any other matter, it should be referred to either the AFL integrity unit or the Queensland Police."
The Lions said they would not make any further comment.