Reed (hamstring) has been downgraded and ruled out ahead of Sunday's matchup against the Eagles, Tim Twentyman of the Lions' official site reports.
The 29-year-old was originally listed as questionable after returning to practice Wednesday, but he'll be sidelined for Sunday's contest. Reed will have now missed the Lions' last six games due to a hamstring injury. He's likely nearing a return, as he practiced in a limited capacity throughout the week, making Detroit's Week 12 matchup against the Giants a possible return date.