Robbie, who played Hagrid in the Harry Potter films, reportedly fell ill with 'flu-like symptoms' on board a flight to Orlando, Florida.
Robbie Coltrane with the other Harry Potter stars in 2004
The 64-year-old was travelling to a Harry Potter convention in the American city, but he became ill on board forcing air staff to let their arrival airport know of his condition.
Upon landing, Robbie was taken immediately to hospital, where he will remain overnight.
Michael Gambone, who played Dumbledore, was said to be travelling with him when he fell ill.
Coltrane's agent has told press that the actor is 'resting' and will be fine - though no more details about his condition have been released.
His agent also slammed claims that the actor had been drinking heavily in the airport lounge ahead of his flight.