Does Breathing Into a Paper Bag While Hyperventilating Actually Help?

Start hyperventilating in a public place and a good Samaritan might just empty the contents of their brown-bag lunch and hand you the bag. According to conventional wisdom (not to mention countless TV shows and movies), breathing into a paper bag is a great way to curb hyperventilation.

So why do we do it—and, more importantly, does it actually work?

What causes a person to hyperventilate?

When you hyperventilate, often during an anxiety or panic attack, you’re breathing so quickly and/or so deeply that you upset the ratio of oxygen to carbon dioxide in your bloodstream: too much oxygen, not enough carbon dioxide. As UCLA Health explains, the influx of oxygen can increase the blood’s pH level to the point that you develop a condition known as respiratory alkalosis, which can cause dizziness, tremors, and other adverse effects. Humans exhale carbon dioxide, so the idea behind the paper bag trick is that you’ll be inhaling the carbon dioxide you’ve just emitted—thus restoring your blood’s pH balance and alleviating those symptoms.

Does breathing into a paper bag work?

Though some people might find success with the paper bag method, there’s a general lack of scientific evidence supporting its effectiveness. Furthermore, it can be dangerous to try if your breathing issues are caused by something other than anxiety—particularly if they're the result of heart or lung conditions. If you’re experiencing shortness of breath because of asthma or hypoxemia (low oxygen in your blood), for instance, limiting your oxygen intake can make things worse, not better. As Verywell Health reports, certain heart attack symptoms—shortness of breath, chest tightness, etc.—are sometimes mistaken for hyperventilation symptoms. If you’re experiencing a heart attack, you also shouldn’t restrict your oxygen intake.

Because the paper bag method might do more harm than good, some experts recommend not trying it at all. And even those who do suggest it as a possible hyperventilation remedy advise an abundance of caution. According to University of Michigan Health, you should only take six to 12 breaths into a paper bag before removing it, and you shouldn’t let someone else hold the bag for you. And if you have “any heart or lung problems”—including coronary artery disease, asthma, and chronic obstructive pulmonary disease—or if you’ve ever had a stroke, a pulmonary embolism, or deep vein thrombosis, avoid the paper bag method completely.

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