Hey Kate,
Welcome aboard. You've come to the right place.
It sounds like you have most of care and feeding of your cluster headaches in hand, so all I can offer at this point is to have the Rx for home oxygen therapy filled... You're missing out on the very best and least expensive abortive available that's safe and has no side effects.
Oxygen therapy at 15 liters/minute is also listed by the National Guideline Clearing House standards of care in treatments for cluster headache below as the first acute therapy of choice by the European Federation of Neurological Societies (EFNS).
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If you want to make sure your Rx for oxygen therapy is written properly, check out the following link that provides the "How To" obtain a properly written Rx for oxygen therapy.
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If you go for a fresh Rx, push for a flow rate of 25 liters/minute when you see your neurologist as this flow rate will support hyperventilation with very safe and very fast aborts. Don't settle for any flow rate less than 15 liters/minute with a non-rebreathing mask. If your neurologist looks at you like you have two heads when you ask for 25 liters/minute show him or her the downloads from the "How To" link.
If you're having 3 or more attacks a day, order the large M-size oxygen cylinders for home use and a couple E-size for work or local travel. At 3 cluster headaches a day I keep three of the M-size oxygen cylinders on hand for a month's supply.
As you can see from the tally sheet stuck to the cylinder on the left, I managed 30 aborts and there was still enough left for one or two more aborts. The M-size cylinders cost $30 each but my co-pay is only $6 so my out of pocket cost/abort per cylinder is 20 cents.
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I also have an aluminum M60 that I use for local travel and work away from home. I also have a trans filler pigtail to re-fill it from the M-size cylinders.
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As you can see from the photo's I use the InGage™ CGA-540 and CGA-870 oxygen regulators from Flotec Inc. The InGage™ is a very rugged regulator that has selectable flow rates from 0 to 60 liters/minute and a DISS fitting for my oxygen demand valve. These are great regulators with an internal cylinder pressure gauge and hand tighten knurled knob so no wrench is required to attach it to the oxygen cylinder.
If I want very rapid aborts (and I do all of the time), I generally start out at a flow rate of 60 liters/minute until I push my system into respiratory alkalosis, then throttle back to 40 liters/minute until I reach the abort.
If I start early, this usually works out to an abort in 2 to 3 minutes with this method using either the O2PTIMASK™ kit or demand valve. If the cluster headache wakes me from sleep and already has a head start up the pain scale, the abort can take from 4 to 7 minutes depending on the pain level. Higher pain levels take a little longer to abort.
I also use either the $27.50 O2PTIMASK™ kit with the 3-liter reservoir bag from the CH.com store tab at the left, or my oxygen demand valve to administer the oxygen. Both work equally well in generating very fast aborts and each has it's advantage.
Take care,
V/R, Batch