Van Gogh drank absinthe, as it was quite common amongst the artist crowd of his time. Research has shown that absinthe of Van Gogh’s time, like modern absinthe, did not contain enough thujone to cause anyone to cut off their own ear. Further, it doesn’t seem feasible to be as prolific an artist as Van Gogh was if he really drank that much.
Van Gogh had serious mental illness. This is the reason he cut off his ear. Absinthia has spent some time in the Van Gogh museum in Amsterdam seeking a connection of absinthe and Van Gogh’s ear, and there isn’t one.