From personal experience, years ago : learning to control your breathing is the key. Your fear of the symptoms can turn it into a self-fulfilling prophecy. When you've deeply internalised the assurance that you can defeat the symptoms any time you like by regulated breathing, you might well find like I did that they just stop happening quite naturally. It takes time and practice. Sometimes now when I find myself in s…
This works unless your anxiety is being triggered by the vagus nerve in which case deep breathing only makes it worse. Had one related to an illness recently, the vagus nerve makes you feel like you are having terrible anxiety that is made worse at the apex of every in/out breath. Then when you can't breathe deeply you start having even worse anxiety. This is the problem I am dealing with atm.
Once your body is full of adrenaline it takes 10 to 15 minutes to physically calm down, there's no shortcut, and often trying to suppress the physical symptoms keeps the cycle going.
What generally works much better is to simply accept that your body is going mad for a few minutes, it's million years old biological systems you don't have any control over, fighting them isn't possible. Keeping a detached mind, breathing normally and remembering that panic attacks don't kill you (the racing thoughts are often the worst thing) helps immensely.