Mozart's drinking runs as a sub-theme throughout the plot in Amadeus. But in reality, it seems that he rarely drank to excess, though in his last year or two his drinking did appear to have increased. During the summer of 1791 when Constanze was in Baden, "he used to drink champagne with Schikaneder all morning, and punch all night." But this report stems from Ignaz Ernst Ferdinand Karl Arnold, who was without firsthand knowledge. While alcoholic writers are legion, the condition seems rare among composers; it is possible that great music was composed under the influence, but not with such consistency or productivity.
Not trying to bust you. Just trying to discern the truth and a quick google turns up no real agreement with the movie version. As for other remarks here about Mozart being poor, that may not be accurate either:
Mozart never went out of style, he never was broke, fallen out of favor, etc., and the bit about being buried in a Pauper's grave?
Well, everyone who was not royalty at that time was buried in mass graves. If you were notable, but not royalty, you got a plaque on the wall of the cemetery, which he did.
The fact is, Mozart was pretty well off for most of his adult life, compared to the average Venetian. He had a billiards table, an apartment with several rooms, and even his own carriage, which was very unusual for even the middle class.
When he died, an audit was performed for death taxes, and it was done by a fellow Mason, who listed the value of his stuff at WAAAAYYYY lower than it actually was worth - as a favor to his widow.
Just as good, right?