I don't believe so, I read in an article on the web that you can fly even if you have oxygen, it can be arranged to use the drop down access if needed on the plane. Obviously he will need to carry his inhalers in his hand luggage but it will be fine as long as it has the prescription label on. I suppose there's no harm in asking your doctor if it gives peace of mind though.

You can have a Oxygen generator on planes, this is what I used when traveling. talk to your DR or your Oxygen supplier.

I can tell you as I have traveled with oxygen, its a small machine they give you special for air planes. Call your provider that handles your oxygen they will get it ready for you. And they drop it off and pick up!

No,you don't need docs permission,carry all meds in hand luggage,also emergency antibiotics and steroids if needed.

It's probably a good idea to check with your doc about whether or not you'll need O2 to fly. There are tests that can be done (High Altitude Simulation Test) to see if you will need O2 at altitude. Planes are usually only pressurized to somewhere between 6,000 and 10,000 feet. Most of us need O2 at the higher elevations, especially if you get up to go to the bathroom. You don't want to be halfway to your destination and develop problems that O2 would resolve!

If you need O2 to fly, you will need to get a Portable Oxygen Concentrator that will meet your needs. Most airlines in the US do not offer O2 in flight any more; nor do most European airlines. There are arrangements you'll need to make depending on your airline. You can usually fine the requirements on their website.