Hospital spokesman Lance Skelly said Saturday that there's no timetable for Lowery to be discharged.
Skelly told the Atlanta Journal-Constitution that doctors are reviewing Lowery's condition "day to day" in deciding when he should be allowed to return home.
Lowery, who stood with the Rev. Martin Luther King Jr. during the civil rights movement, was admitted to the hospital a week ago with a blood clot in his lung.
The 88-year-old offered the benediction at President Obama's inauguration last year and received the Presidential Medal of Freedom months later.
Lowery co-founded the Southern Christian Leadership Conference along with King.