If I start feeling irritable, I take L-Theanine and valerian root. They do a good job of calming me down.

If I get irritable with a co-worker, I try to find someplace where I could be alone--I isolate myself physically for a short time (for example, the restroom) think about the situation, and find a reasonable method to resolve the conflict.

It's generally not a good idea for a man to be overly emotional at work--makes him look bad.