Almost everybody gets angry now and then. The reasons are legion and, of course, the anger doesn't have to have anything to do with mental illness. When it does, though, its expression can be magnified, irrational and/or out of control.
Irritability and anger can be part of bipolar depression, hypomania and mania. It can go from just going around grumbling and snapping to punching walls - or people.
I myself can be irritable, but rarely for an extended period. As for anger - I first had...

