There are many things that can cause us to be irritable: Low blood sugar. Stress. Chronic pain. Depression, Anxiety. Our need to be in control. And many other things. When we are irritable, we tend to take it out on others and this abuse can lead to relationships failing. Consequently, it behooves us to recognize when we are irritable and do the best we can to address the causes and control our irritation so it does not leak out onto other people.