go bananas
Act crazy, as in When it comes to animal rights, some people go bananas. According to the lexicographer J. E. Lighter, this expression may allude to the similar go ape, in that apes and other primates are closely associated with eating bananas. [Slang; second half of 1900s]
Related Words for go bananas rant, babble, fume, orate, declaim, prate, storm, harangue, rage, roar, thunder, rail, splutter, gabble, mouth, perorate, prattle, jabber, wander, bloviate