Matt Richardson has revealed that he is suffering from amnesia after having an infection.
He said he was hoping that his memories would return.
Sharing a photo from the concert, Richardson wrote: "My brother and I went to see Green Day in Dublin last week.
"And I sadly can’t remember it as I’ve had a lovely infection which caused some wonderful affects to my brain and loads of amnesia.
"After a really cool trip to hospital I’m trying to piece it all together again."
The comedian and TV star, 31, quipped: "Hopefully the memories come back but if I owe you money, sorry you’re on your own x."
Fans flocked to send messages of support to the star, who is also known for presenting X Factor's spin-off Xtra Factor.
"Get well soon champ," one posted, while another fan said: "Really hoping you are ok!"
"Oh no how scary!" said another.
"Love you Matt, must be such a confusing and horrible experience," said someone else.
One of the TV star's followers wrote: "As someone who suffers from epilepsy I feel your pain.
"I’ve lost many years from seizure induced amnesia, including many gigs.
"Hopefully yours will return soon!"
Model Sam Rollinson, who Richardson is dating, posted: "You owe me 7 hours at a very expensive spa - to pay for the harrowing 7 hours at A and E."
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