Pope Francis, who has been suffering from influenza, has been taken to a hospital in Rome for a check-up, Italian news agency ANSA reported on Wednesday.
The 87-year-old pontiff had earlier skipped a reading at his Wednesday weekly audience, delegating the task to an aide and telling the faithful he was still not well.
The pope, who has had a number of health issues recently, had cancelled appointments on Saturday and on Monday due to what the Vatican called a mild flu.
On Sunday, he addressed crowds in St Peter's Square as normal, to deliver his Angelus message.
"Dear brothers and sisters, I still have a bit of a cold", Francis said at the audience on Wednesday, announcing that someone else would read his catechesis on envy and vainglory, two of the seven deadly sins.
The reading was about one page long.
The pope did speak at the end of his audience, his voice sounding hoarse and coughing a bit, to greet some of the faithful and issue calls for peace, as is customary.
In December, the pope was forced to cancel a planned trip to a COP28 climate meeting in Dubai because of the effects of influenza and lung inflammation.
In January, he was unable to complete a speech owing to "a touch of bronchitis". Later in the month he said he was doing better despite "some aches and pains".
As a young man in his native Argentina, Francis had part of a lung removed.
The pope also has difficulty walking, and regularly uses a wheelchair or a cane. On Wednesday, he arrived at his indoor audience in a wheelchair.
