Foster, 31, picked up a knock on Tuesday and has now been sent back to his club as a precaution.
He will play no part in Wednesday night’s friendly with Norway at Wembley.
"England goalkeeper Ben Foster picked up a knock in training on Tuesday and has returned to his club for treatment as a precautionary measure," said a statement from the FA.
"West Bromwich Albion will provide further guidance on Ben Foster. At this time, England manager Roy Hodgson will not call up any replacements."
West Brom said their medical team were assessing the problem.
"We will spend the next few days letting it settle down and then assess it again - but at this stage we are optimistic it is not a serious problem," director of football administration Richard Garlick told the club’s website.
"It made sense for Ben to take no chances."
Manchester City's Joe Hart is Hodgson's first choice and will start against Norway, and in Monday's opening Euro 2016 qualifier in Switzerland, with Southampton's new signing Fraser Forster his deputy.