4. Rebreathing
Another solution for panic attacks and hyperoxia, in general, is to try rebreathing. Here, you take a paper bag and then hold it over your face and nose to breathe into.
The idea is that you’re going to use up all of the oxygen in the paper bag, leaving you with a bag of carbon dioxide. Now you’ll be breathing that and as you do, the levels of oxygen in your brain will return to normal!