Hey Becky,
This isn't an isolated problem.
Too many PCPs and Neurologists still refuse to prescribe oxygen therapy as an acute treatment/abortive for cluster headache and that frustrates all of us who know how well it works to abort our cluster headaches.
The attached abstract from the cluster headache survey many of us took (1134 to be exact) in 2008 gives a breakdown why physicians refused to prescribe oxygen therapy.
The abstract also lists oxygen therapy as being 70% effective in aborting cluster headache. This figure is consistent with the latest study of oxygen therapy by Dr. Peter Goadsby.
The following link provides the EFNS guidelines on the treatment of cluster headache and other trigeminal-autonomic cephalalgias. You'll note that oxygen therapy is at the top of the list of acute treatments for cluster headache. You might want to print a copy of this standard of care for cluster headache and take along for your next appointment with your neurologist or send him an email with the link and the attached abstract.
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When you do finally see your neurologist ask him what oxygen flow rate he prescribed that didn't work and did he specify a non-rebreathing mask? Finally you might ask if he provided any training for his patients on how to use oxygen therapy effectively? The home oxygen delivery folks will not provide this training out of fear of litigation. They'll only show you how to attach the regulator to the oxygen cylinder and oxygen mask tubing to the regulator.
Finally, I own my own 0-60 liter/minute regulator, Oxygen demand valve, and O2PTIMASK™ kit so my cost per abort before insurance worked out to $1.00... With insurance, my co-pay worked out to 20 cents/abort. Contrast that with a 6mg. stat pen shot of imitrex that costs costs $80... an imitrex 12mg. nasal spray that costs $20 per abort and a 25mg. imitrex tab that costs $7 and you'll see that oxygen therapy has a much greater bang for the buck.
Using oxygen flow rates that support hyperventilation (≥25 liters/minute) oxygen therapy is nearly 100% effective with abort times averaging 7 minutes depending on the pain level. Abort times this short rival imitrex injections but there's no side effects with oxygen therapy...
Take care,
V/R, Batch