I think this is the most instructive clue I have found, (Laertius 4.44):
"[Arcesilaus] died in a fit of madness, as Hermippus says, after drinking a good deal of unmixed wine, he had by then reached the age of seventy-five, and no man was more highly regarded by the Athenians."
That alone is only suggestive (just like the example with Epicurus), however the very next line, Diogenes says:
"My own verses about him run as follows: Why, Arcesilaus, did you draw unmixed wine so unsparingly as to take leave of your sense? I pity you not so much for your death..."
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As a side note about Arcesilaus being "highly regarded," Plutarch says "The reputation of Arcesilaus seems to immoderately distress Epicurus -- given that [Arcesilaus] was especially admired among the philosophers in those times" Plutarch (fl. 80 CE), Against Colotes, 26, 1121 E fin.
Arcesilaus was a pupil of both Theophrastus and Pyrrho, yet he ended up leading the Academy a few years after Epicurus died.