There is an explanation for all experiences of anger. Anger is an emotional response to your thoughts, related to a situation or event. Sometimes it is difficult to identify the thoughts that trigger the emotional response but they exist.
One of the priinciples of Cognitive Behavioral Theory is that thoughts elicit an emotional response and a corresponding behavior is motivated by the emotion. An example would be you are driving down the road and someone runs through the intersection, for which you have a green light, cutting you off and causing you to skid to a hault. You think to yourself, What an idiot! He should have seen he had a red light and I had the right of way. You then lay on the horn, shout some explicatives and communicate your displeasure with sign language. First, examine how the thought led to anger. It indicates that he wronged you, that you had the right of way. You believe that he "should" have seen the light, indicating that he most likely ran it, knowing it was red and you also assumed he was an idiot. All these are plausible thoughts but you cannot be certain of any of them. He may be a genius with an IQ of 180 whose breaks had failed from no fault of his own and the situation was out of is control. If this was the case and you were aware of it, your emotional response may have been different. In any case, the way you think determines how you feel. There are always thoughts underlying our emotions.
To deal with it, identify the thoughts. Then spend some time searching the web for information on Cognitive Behavioral Therapy, irrational thoughts related to anger, challenging irrational thoughts, and anger coping skills. You may also seek out a therapist to help you learn some skills.
I realize that their may be other psychological issues and possibly stress that is contributing to your anger but CBT techniques and coping skills will still apply. If it is episode related, you may also contact your psychiatrist to discuss medication options.
If you do a search on this site, with the serch term 'anger' you will find an informative article by John, called "Breaking Down Bipolar Anger."
A wonderful skills and mindfulness program called DBT, Dialectical Behavior Therapy works very well with anger and any emotion that one feels is dysregulating. I know in my own life and that of my patients anger is a mask for hurt and other emotions that are too sensitive for us to handle.
Being mindful of the anger, and using what is known as a chain analysis works well in helping one to figure out where it started and how you got there; More it helps you to figure out how to stop it next time it happens.
If you would like I would be happy to help you with the chain. Just email me and I will send you a copy of it and an explaination of how to do it. Being mindful takes work, but it sure beats the alternative.