Van Gogh had Menière's disease and not epilepsy.

We intend to correct the historical error that Vincent Van Gogh's medical problems resulted from epilepsy plus madness, a diagnosis made during his life but for which no rigid criteria are apparent. Review of 796 personal letters to family and friends written between 1884 and his suicide in 1890 reveals a man constantly in control of his reason and suffering from severe repeated attacks of disabling vertigo, not a seizure disorder. His own diagnosis of epilepsy was made from the written diagnosis by Dr Peyron, the physician at the asylum of St Remy (France), wherein on May 9, 1889, Van Gogh voluntarily committed himself to the asylum for epileptics and lunatics. However, the clinical descriptions in his letters are those of a person suffering from Meniere's disease, not epilepsy. The authors point out that Prosper Meniere's description of his syndrome (an inner-ear disorder) was not well known when Van Gogh died and that it often was misdiagnosed as epilepsy well into the 20th century.