I hope you feel better soon. Christina has some great suggestions.

I've never had what I considered a rage but I've had several months of hypomania with an edge to it. A slightly aggressive feeling underlying inside me. I never expressed it but I felt it. I was mindful of it, especially, if someone irritated me...how should I react, pause, think, etc. Maybe that will help you?

My pdoc recommends screaming into a pillow or punching it when angry.

Keep us posted and hang in there.