Hey Bud,
Welcome aboard. Your episodic cluster headache attacks sound typical and three years for a good diagnosis is almost average... It took me nearly 4 years to get a a diagnosis.
Where in Washington do you live? I grew up in Tracyton, halfway between Bremerton and Silverdale, WA.
You should get a prescription for oxygen therapy. Oxygen works well for most cluster headache sufferers as an abortive if used properly and is a lot less expensive than imitrex. If you can get a prescription it should read like the following:
"Oxygen Therapy: 100% O2 with a non-rebreather mask at 12 to 15 liters/minute AS NEEDED for cluster headaches."
The Rx covers the bases with both the medical insurance companies and also the home oxygen delivery folks. If there's no mention of cluster headaches, most medical insurance companies will assume a COPD disorder and require an additional written statement from your doctor that provides your oxygen saturation levels. Dumb but that's the way they do it. The NRB oxygen mask and 12-15 liter/minute flow rate will ensure your home oxygen delivery folks give you a regulator capable of the needed flow rate and a proper mask instead of a nasal canula and a regulator that will only provide up to 8 liters/minute.
Pred tapers are great as a transition therapy and occasional cycle buster, but that's as far as they go. Prednisone is the worlds best worst drug. A great anti-inflammatory, but the side effects can be and usually are bad if taken for much more than a few weeks.
It sounds like you've got a good doc so you may be able to show him the latest strategy in treating cluster headache sufferers. Print and take or email the following links to him for your next visit:
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This first link provides a comprehensive treatment strategy with an abortive therapy, a transitional therapy, and a preventive therapy. The next two links provide some great insights on the benefits of oxygen therapy.
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The neurologists at the Michigan Headache & Neurological Institute (MHNI) see hundreds of cluster headache sufferers every year so have a lot more current first hand experience than most neurologists. I've met with Dr. Rozen there in Ann Arbor, MI and they don't come any better.
The good news is oxygen therapy works exceptionally well for most of us if used properly at a high enough flow rate. It will give you back your life once you master its use and gain the upper hand over the beast.
Take care,
V/R, Batch