The 50-year-old actor was taken to the accident and emergency ward of a hospital in west London after the health scare, reported the Sun online.
The 'Notting Hill' star, who waited at the Chelsea and Westminster hospital without making any fuss, refused to call an ambulance as he preferred not to waste paramedics' time.
"You'd have had no idea he was a huge star," said a source. Grant was later discharged and is now recovering at home.
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