The 20-year-old went to ground 73 minutes into the match and was quickly treated by medical staff, before then being taken to a local hospital by helicopter.
CPR was said to have been performed on the youngster, leaving his teammates looking on horrified, but his condition has since been described as stable.
A club statement, released via Twitter, read: "Abdelhak Nouri became unwell today during our friendly match vs. Werder Bremen. After a successful reanimation on the pitch he was transported to the hospital, where he remains in stable condition."
Nouri has played nine league games for the Dutch giants and was part of the squad that lost to Manchester United in last season's Europa League final.