It's almost as if prescription drug marketing were inherently a severe conflict of interest that represents a danger to public health, and should therefore be much, much more tightly restricted.
Prozac was created for use as an anti-psychotic but filed with the FDA for use as an anti-depressant. Because there are soooo many depressed people which means more money for the same drug. Wikipedia says it is the 23rd most prescribed drug in the US(wtf).
Do you have a source for that? I couldn't find any mention of that in the Wikipedia article (https://en.wikipedia.org/wiki/Fluoxetine#History), and it seems, from the history I've tracked down, like SSRIs were specifically developed with an intent to treat mood disorders.
There does seem to be a combination drug that includes prozac and olanzapine that's used to treat psychotic disorders. It's been on the market for a while; maybe that's resulted in some confusion?