Varney was signed by former Rams manager Paul Jewell in November 2008 on a loan deal from Charlton that became permanent in January 2009. He has only made 14 appearances and scored just one goal.
Varney is currently in his third loan spell at Wednesday, where he has scored nine goals in 32 outings for the Yorkshire club.
He concedes he may be forced to quit Derby to resurrect his career and admits he would be interested in a move to Leicester.
"I suppose I'm in the shop window. Of course, I'd love to come to Leicester," Varney told the Derby Telegraph. "I feel I've not really been given a chance at Derby."