Pearson had been feeling unwell on Saturday morning but was able to attend his team's match at Blackburn.
He was advised to go to hospital after that game and remained there whilst doctors carried out further tests.
But the 50-year-old has been given the all clear and is expected to take charge of Leicester's match with Yeovil on Tuesday.
An earlier statement from Leicester read: "On Saturday morning, Nigel was suffering from sickness, however he wanted to oversee our fixture against Blackburn Rovers - where the club extended its unbeaten run to 17 games.
"After the match, Nigel took the decision to seek medical advice and to attend hospital for tests, as a precautionary measure. He remains in hospital at this stage and will undergo his final tests on Monday morning.
"The club would like to extend its thanks to the staff at Blackburn Rovers for their assistance on Saturday and to our fans for their concern for Nigel."