The 78-year-old was taken to Cedars-Sinai Medical Center for the 'ongoing health problem', spokesperson Sally Morrison said.
It is not clear how long she will be in hospital, Ms Morrison added.
Dame Elizabeth has a long history of medical problems and underwent heart surgery in 2009.
'Her family and close friends are appreciative of the warm support and interest of her loyal fans but have asked that people respect her privacy and allow her medical team the time and space to focus on restoring her back to health,' a statement issued on Friday said."