Lacy was knocked out after a helmet-to-helmet collision with Washington Redskins safety Brandon Meriweather on September 15, a hit that resulted in a $42,000 (£26,000) fine for the Redskins player.
However, he took part in full practice on Monday after the Packers had a bye week and is expected to return to the side for Sunday's match against the Detroit Lions.
"I thought Eddie practised well today, so it was good to have him back out there. He's full go, and I think the week off definitely helped him," Packers coach Mike McCarthy told reporters.
The Packers are currently 1-2 for the season after their defeat by the Cincinnati Bengals.