Depression, anxiety, trauma, and substance use also increase irritability and anger and unfortunately anger is a pretty tricky emotion. One of the trickiest things about it is that it's a secondary emotion - meaning it only comes out in response to other emotions. This is largely because anger is an emotion that exists to protect us. However, this same quality is why expressing anger alone will not often release our anger - it's because the only thing our anger wants is the submission of whoever or whatever it is aimed at. The anger wants submission even though the primary emotions that lead to the anger typically want something entirely different.
The primary emotions leading to anger are typically something like: hurt, shame, sadness, frustration, fear, anxiety, etc.
Expressing the primary emotions beneath the anger will be far more relieving to anger than expressing anger itself.
Anger often stimulates more anger.
So, if you don't yet feel out of control, I would recommend sharing all the primary emotions except for anger first, then share the anger. This has two benefits: first it helps soothe you a bit by expressing the emotions that might lead to anger, second it helps the listener understand what caused your anger which usually reduces their defensiveness and increases empathy (depending on how escalated they are).
If you're starting to feel out of control, it's probably better to try and help yourself deescalate first. One option is to stay in the conversation and try to slow your breath as well as take a moment to step back from your thoughts and feelings to try and regain some objectivity.
For most of us that's extremely hard though, so that leaves three options: time, distraction, or shocking the body (not with electricity).
For time, explain why you need to leave and do so for at least 20 min (it takes that long to soothe enough that your adrenaline and other bodily systems don't return to anger as easily). During that time you also want to do something calming. If you continue to play the argument over and over in your mind, don't start 20 min till you stop doing that. Then, once you're calmer, go back, see if the other person feels ready and share the primary emotions first, followed by your anger.
Distraction usually attempts to use our frontal lobe and therefore our body tries to send blood back to the frontal lobe to help us solve the issue. Otherwise, as we anger our body prepares for a fight by bringing the blood flow in our brain to the center. More on this later. If we're too triggered it might be challenging to distract, but if that doesn't work you can pull out the super effective tool: shocking the body.
Shocking the body means dipping your face in cold water or pressing ice packs to your face for at least 30 sec. Another alternative is to do high intensity cardio for a brief moment. Either of these should help diffuse the anger pretty rapidly.
If you want a more concrete indicator of when to use time, distraction, or shocking the body, try to measure your heart rate (or look at your fitness monitor). Any heart rate over 100 BPM probably means it's time to go cool off rather than keep talking. Above 100 BPM a process known as Diffuse Physiological Arousal (DPA) starts, and your IQ measurably drops off at a pretty rapid rate as your heart rate increases. What it means is the blood is leaving your frontal lobe (where you do your thinking), and going toward your limbic system (your more ancient, emotion-driven, "animal" brain). More on those systems in another post, but that's when your mind starts being blank and you start getting impulsive. At that point, we're really just going to struggle to do or say anything beneficial to ourselves or our relationships because we'll lack access to the constructive, logical part of our brain. Some heart rate monitors allow you to set an alarm when your heart rate rises to a certain BPM. If you have this feature, maybe set it at 100 BPM for a couple weeks and get a feel for what 100 BPM feels like in your mind when you're angry so you have a reference point for when to stop the conversation.
I hope that helps! It's easier said than done, but when implemented these steps can be of great help to feeling less caught in the anger trap!