Princess Charlene is in a "stable" condition after "suddenly collapsing" on Wednesday, the palace has confirmed.
In a statement issued on Friday, the Palais Princier said: "On the evening of September 1, Her Serene Highness Princess Charlene of Monaco was taken to hospital after fainting due to complications from a serious ORL infection.
"Her Highness is closely monitored by Her medical team who said that Her condition was not worrying."
WATCH: Princess Charlene and Prince Albert share highlights from their relationship
Charlene was discharged on Thursday and returned to the lodge where she has been staying.
READ: Princess Charlene is 'ready to come home' reveals Prince Albert
She has remained in South Africa since May after she came down with an ear-nose-throat (ENT) infection. Charlene was reunited with her husband, Prince Albert, and their six-year-old twins, Prince Jacques and Princess Gabriella last week, following a four-hour operation on 13 August.
In his first interview since returning from visiting his wife in South Africa, Albert, 63, told PEOPLE magazine on Thursday of Charlene: "She's ready to come home."
Charlene has previously said that she is hoping to travel back to Monaco in October, but Albert tells the publication that "depends on what her doctors say," and if her progress continues, she could be back as soon as this month.
"I know she's said possibly 'late October,' " Albert said. "But that was before this most recent round of appointments. I'm pretty sure we can cut that time frame a little short."
MORE: Princess Charlene of Monaco cosies up to Prince Albert in loved-up photos
MORE: Princess Charlene of Monaco 'thrilled' to be reunited with Prince Albert and their children after operation
Charlene pictured with her family in 2020
The princess shared some sweet photos of her reunion with her family on Instagram last week, revealing that she was "thrilled" to have them back with her.
In July, Charlene and Albert spent their tenth wedding anniversary apart, with the palace sharing video highlights of their marriage.
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