France winger Menez was replaced in the first half of the 2-1 league home loss to nine-man Stade Rennes on Saturday after he picked a thigh problem.
PSG did not specify what injury Gameiro had.
The French side will join group leaders Porto in the last 16 if they do not lose against a Kiev team they thrashed 4-1 at home in September.
Get the best features, fun and footballing frolics straight to your inbox every week.
Thank you for signing up to Four Four Two. You will receive a verification email shortly.
There was a problem. Please refresh the page and try again.