Matt,
What you're experiencing with oxygen therapy is very common. Most CH'ers experience an increase in the frequency of their cluster headaches after starting oxygen therapy.
Fortunately this initial increase in frequency is usually accompanied by a decrease in intensity and the frequency of attacks starts to drop after a couple weeks of using oxygen therapy.
If you're having more than 3 cluster headaches a day, you're money ahead ordering at least three of the larger M-size oxygen cylinders as a one month supply. The average cost of an M-size oxygen cylinder refill is $30 before insurance and you should get 20 to 25 aborts per cylinder. An E-size oxygen cylinder costs $20 before insurance and they're usually only good for 3 to 4 aborts. Do the math... Oxygen therapy is also far safer than the triptans and a lot less expensive.
Try asking your home oxygen supplier for a regulator that's capable of 25 liters/minute when you ask for the three M-size cylinders. If they refuse, ask your doc to phone in a change to your Rx for a flow rate of 25 liters/minute and for the larger M-size oxygen cylinders.
A flow rate of 25 liters/minute will support hyperventilation if you're able to remain still during the therapy. Most successful oxygen therapy users buy their own regulators capable of 0 to 25 liters/minute and some go for even higher flow rates with regulators capable of 0 to 60 liters/minute. They also use the O2PTIMASK™ kit available from the CH.com store at the left for $27.50. I've had the same one for nearly 3 years and it works just fine.
You can always buy your own 0-25 liter/minute regulator. They're readily available over the Internet. Make sure you order one with a CGA-540 fitting to match the fill fitting on the larger M-size oxygen cylinders.
The photo below shows my home oxygen therapy kit with one of the 0 to 60 liter/minute InGage™ regulators from Flotec.
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As you can see, I use both the O2PTIMASK™ and a demand valve. Both are equally effective and each has it's advantages. You can also see from the tally on the sticky that I got 30 aborts from one M-size oxygen cylinder. I've also found breathing straight from the 22mm coupler on the O2PTIMASK™ and demand valve provides less resistance at the higher respiration rates that support hyperventilation.
As far as feeling trapped at home to stay near your oxygen there are a few things you can try.
The first is to get a "roadie" or portable oxygen cylinder. When you ask your supplier for the M-size oxygen cylinder tell them you still want to keep at least 2 or 3 of the E-size oxygen cylinders for local travel, work and other activities away from home.
I purchased the aluminum M60 shown below as my roadie and refill it from the larger M-size cylinders. It holds 1700 liters when fully charged and weighs 23 lbs. It's also good for 10 to 12 aborts so it gives me a good three day supply away from home.
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You can also try a change in diet. Cut back on red meat and bread and instead eat more cold water fish, chicken, lots of green veggies and fresh fruit.
You might also ask your doc about taking calcium citrate tablets that contain vitamin D3, magnesium and zinc washed down with lemonade. This combination acts as a buffering regimen that many of us found tends to decrease the frequency and intensity of our cluster headaches.
When you call your doc, ask about taking up to 10,000I.U. vitamin D3 along with 2000mg. Omega 3 Fish Oil a day. This combination acts as an anti-inflammatory regimen that some of us have found decreases the frequency of our cluster headaches.
Hope this helps.
Take care,
V/R, Batch