Westbrook, already out for Sunday's game against Chicago, was examined Wednesday by concussion specialists at the University of Pittsburgh Medical Center. After that exam, Dr. Joseph Maroon and Dr. Michael Collins said Westbrook was making encouraging progress and would be re-evaluated in two to three weeks.
"I think the doctors want to see how he does after two weeks, what kind of symptoms he has, and then they'll just go back through and evaluate him after that -- two to three weeks," Reid said, according to the report. "We'll just see how he feels after that."
Westbrook was back at the Eagles' training facility Thursday but is not expected to resume activity until next week at the earliest, according to the report.
"We're backing off this week, just letting him rest," Reid said, according to the report. "Next week, he can start going to meetings and some things. We'll see how he feels as he goes."
Westbrook, a key element in the Eagles' offense, suffered a concussion Oct. 26 in a game against Washington. He sat out for two weeks, but suffered a second concussion Sunday in his return to the lineup at San Diego.
Rookie running back LeSean McCoy will start in Westbrook's absence.
Information from The Associated Press was used in this report.