He had eccentric personalities, unstable moods, and experienced psychotic episodes and he eventually committed suicide at the age 37.

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Despite limited evidence, well over 150 physicians have ventured a perplexing variety of diagnoses of his illness. Henri Gastaut, in a study of the artist’s life and medical history published in 1956, identified van Gogh’s major illness during the last 2 years of his life as temporal lobe epilepsy precipitated by the use of absinthe in the presence of an early limbic lesion. In essence, Gastaut confirmed the diagnosis originally made by the French physicians who had treated van Gogh. However, van Gogh had earlier suffered two distinct episodes of reactive depression, and there are clearly bipolar aspects to his history. Both episodes of depression were followed by sustained periods of increasingly high energy and enthusiasm, first as an evangelist and then as an artist. The highlights of van Gogh’s life and letters are reviewed and discussed in an effort toward better understanding of the complexity of his illness.
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The lead in the paint drove many artist nuts, a technique to make the tip of the paint brush come to a fine point was/is to put the hairs of the brush in your mouth using your tounge to bring the hairs together making a fine tip point,then you can dip the tip into the paint getting just enough on it for a fine application. The brush would still have traces of lead paint on it, after doing this for years you can only imagine how much lead they've injested.