Yesterday he maintained his drink had been spiked.Police went to Rushcutters Bay Park after reports of a man bashing his head against a fence about 3.20pm.
Police say McKenney was unconscious and covered in blood from facial cuts.
After ambulance officers treated him, police asked whether he had any illicit substances and he allegedly replied, "Just some GHB".
In his pocket he had a glass vial with 20ml of a clear substance, which police will test.
Drug expert Paul Dillon said this was about 10 doses, with a street value of $35-$40 per dose.
Sydney St Vincent`s Hospital emergency department director, Prof Gordian Fulde, said one dose of GHB usually lasted three to four hours.
McKenney has vowed to fight the drug allegations. He thanked his Sydney radio breakfast show listeners for their support.
