The term 'loses it' is used to describe someone who is losing their temper or composure. This can be expressed in a variety of ways, such as ranting, freaking out, snapping, panicking, getting mad, exploding, going ape, going mad, having a cow, having a fit, flipping out, going gaga, blowing a fuse, throwing a fit, and going bananas. All of these terms are related to the idea of someone becoming overwhelmed with emotion and losing control.