Jeff Howe of The Athletic first reported that Andrews was hospitalized and is expected to miss a "significant amount of time."
Andrew has appeared in 46 of 48 regular-season games over the past three seasons, starting every single contest in which he has played.
Andrews had missed the last two practices with the Patriots uncertain about his status.
When asked if everything was okay Monday, offensive line coach Dante Scarnecchia responded, "We'll find out," per Zack Cox of NESN.
The Patriots will also have to learn how to play without one of their more reliable players, a team captain who has started in each of the team's last two Super Bowl wins. The undrafted player took over the starting job during his rookie year and has continually earned the trust of Tom Brady.
Ted Karras is expected to take over at center after serving as a reliable backup at center and both guard spots during the past three years. He's entering the final year of his rookie contract and could use this time to showcase his ability to either New England or someone else who can sign him in the offseason.