Boski,
High oxygen flow rates do not cause lung damage... That's an old wives tale.
Navy and Marine Corps pilots have been breathing 100% oxygen while flying tactical fighter and attack aircraft from takeoff to landing for over 70 years and there have been no documented cases of lung damage. They all get annual flight physicals with chest X-rays so any lung damage would show up if it was there... I might add that these pilots and air crew frequently breath that 100% oxygen at flow rates greater than 40 liters/minute...
In fact, it's a US Navy regulation that all pilots and aircrew flying in ejection seat equipped aircraft breath 100% oxygen from takeoff to landing... and they're flying $35 to $60 Million dollar aircraft... I don't think the Navy or Marine Corps would make this a requirement if it was dangerous...
I've over 3000 hours flying Navy fighters on and off aircraft carriers, and all of that flight time was spent breathing 100% oxygen on missions lasting more that two hours and a few as long as 7 hours... I can tell you first hand that during air-to-air and air-to-ground combat missions where high G-forces are common, a flow rate of 40 liters/minute and higher is very common...
I'm still here at 65 and I've also been using high flow rate oxygen therapy that supports hyperventilation for more than 5 years. With the exception of an occasional snort of imitrex nasal spray during airline travel, oxygen is all I use... No other prescribed cluster headache medications. I also still get annual physicals and pass them just as easy now as I did during 24 years of Naval Service.
Starting oxygen inhalation therapy at the first sign of an approaching cluster headache is the only smart thing to do. The longer you wait, the higher the pain climbs, and higher pain levels take longer to abort.
For example a cluster headache that reaches Kip-3 during this method of oxygen therapy will take 3 minutes to abort. If the cluster headache reaches Kip-6 it will take an average of 7 minutes to abort and a Kip-8 will take an average of 12 minutes to abort.
These are very repeatable results proven with the data collected by 8 cluster headache sufferers on 366 aborts with this method of oxygen therapy. The bottom line is START OXYGEN THERAPY EARLY!
Getting hit while at work or while on the road during local travel is another issue, and yes, IQ drops rapidly when the beast starts hammering out a tattoo on the back of your eye... However, a little prior planning and a little training makes this much less a problem as you'll gain a lot of confidence knowing you can abort your attacks with this method of oxygen therapy.
I keep three M-size oxygen cylinders at home and I have an aluminum M60 for local travel. It holds roughly three times the volume as a 700 liter E-size portable oxygen cylinder so it's good for two to three days at three hits a day.
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My home oxygen therapy kit
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My "Roadie" that I fill myself with a transfiller rig
New York can be a problem... but if you don't mind a ruck pack or fanny pack, you can carry two of smaller composite epoxy oxygen cylinders good for one or two aborts each and refill them at home.
The high cost of oxygen, as you put it, is a red herring... Most M-size oxygen cylinders cost $30 per refill. I have a 20% copay so my cost is $6 per M-size oxygen cylinder and I get an average of 30 aborts from one of these cylinders so my out of pocket cost per abort is 20 cents... The last time I checked... an imitrex stat-pen injection costs around $80 before insurance...
If anyone was foolish enough to stay on 100% oxygen for 12 hours continuously with out any breaks breathing normal air, they would start feeling the symptoms of pulmonary oxygen toxicity, but these symptoms would clear rapidly with no lasting effects after a few minutes of breathing normal air.
Now... With the myths dispelled and out of the way... When are you going to give oxygen therapy another try? I'll be glad to help.
Take care,
V/R, Batch