The former Blackburn Rovers midfielder has re-emerged as a doubt for Ireland's upcoming World Cup qualification fixtures against Sweden and Austria
The 32-year-old had been making progress on his thigh injury and was set to make a return to the international fold but has been forced to see a specialist after hurting his Achilles tendon.
"Keith is down to see a specialist on Monday so we will have to wait and see what happens on that one," Bolton boss Dougie Freeman told reporters.
"The thigh problem he had is okay now but his Achilles is still little bit sore. He is a still a couple of weeks away I think."
The set-back means that Andrews is likely to miss Ireland's World Cup qualifying fixtures against Sweden on March 22 and Austria on March 26.