Yes. Oxygen can be a lifesaving treatment for people with severe asthma.
Some research has shown it’s best not to breathe in pure (100 percent) oxygen when you have severe asthma. Breathing in a lower concentration than 100 percent oxygen works better.

How can it help?

Breathing in extra oxygen through a mask helps get oxygen into your bloodstream while you’re recovering from your asthma.
One study has found that you’ll be able to breathe better if you don’t breathe 100 percent oxygen in the A&E department, but breathe a lower concentration.

How does it work?

Every cell in your body needs oxygen to work properly. If you don’t get enough oxygen, you’ll pass out eventually and you may die.
If your asthma gets very bad, you’ll find it hard to breathe. So you won’t get much air into your lungs. And your body won’t get the oxygen it needs.
So breathing in extra oxygen should help get enough oxygen into your bloodstream and around your body.

But oxygen is unlikely to harm you. It could save your life.