George IV was portrayed in the movie, “The Madness of King George” which was actually about his father, George III. Quite a good movie. In fact, I referenced it when comparing George III to the DUmmies. Both made efforts to APPEAR sane.
As far as is known, George IV was not afflicted with the same mental ailment as his father, George III. George III had something in his body chemistry where red meat and the composition of blood didn't get along, causing the brain to go haywire. For a bullheaded Hanoverian, George III was probably actually the best of them all.
His oldest son, who became George IV in old age, on the other hand was noted for debauchery and decadence.
Don't be fooled by the pictures of the handsome pair above; those pictures are from circa 1800, about twenty years before the coronation of 1821. By 1821, both were fat and seedy. George IV looked very much like Fat Che--without the sourness, bitterness of expression--and was about the same size (maybe a couple of inches taller), a behemoth whose enormous belly sagged in front of him as if an apron.