Synonyms for Lose one's cool:

• v.

  •become insane (verb)
  • go crazy.
  •freak out (verb)
  • blow a gasket,
  • wig out,
  • hit the ceiling,
  • go ballistic,
  • flip out,
  • blow one's top,
  • blow one's mind,
  • go haywire,
  • go off the deep end,
  • lose one's composure,
  • crack up,
  • break down,
  • lose it,
  • flip one's lid,
  • come unglued,
  • lose control of oneself,
  • go bananas,
  • work oneself up,
  • go berserk,
  • fly off the handle,
  • blow one's stack,
  • lose one's temper,
  • go ape,
  • freak out,
  • go nuts,
  • lose one's mind.
  •go crazy (verb)
  • go daffy,
  • go psycho,
  • go buggy.

• Other synonyms:

  •freak out
  • lost it,
  • going off deep end,
  • breaking down,
  • going berserk,
  • blowing a gasket,
  • going ape,
  • go off deep end,
  • blowing one's top,
  • blow mind,
  • lose temper.