An ambulance was called to the home of Kagawa on Wednesday night when the midfielder complained of breathing difficulties hours after his appearance in the champions' defeat to Everton at Old Trafford.
An ambulance spokesman told The Sun: 'We arrived at the scene within seven minutes to treat a person for breathing difficulties."
After paramedic care the £17m signing did not need hospital treatment.
A club source told The Sun: "He had a bit of a turn but he's ok now."
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