Hey Bob,
Ufdah!!! Not many CH'ers from Snus Junction... (Poulsbo, WA for the rest of you unfamiliar with the Pacific NorthWest)... It's a Norwegian enclave North of Bremerton and across the sound from Ballard, WA, a suburb of Seattle... a.k.a. Norwegian Central for the old timers...
I grew up in Tracyton and went to Central Kitsap... U of W after that...
Please let me start from the top on your post... If you're using oxygen therapy at flow rates that support hyperventilation, you should be knocking down cluster headache attacks at Kip-6 to Kip-7 in 6 to 7 minutes...
However, your comment about O2... "I’m feeling that it’s helping," leads me to suspect that you're using a much lower flow rate ≤15 liters/minute.
We've collected a lot of data on aborts with oxygen therapy that clearly shows an oxygen flow rate of 25 liters/minute is the minimum that supports hyperventilation and that higher flow rates are even more effective in providing reliable and short abort times...
Regarding taking verapamil or not... That's really a call between you and your doctor... It's the leading preventative listed in most standards of care and treatment for our disorder as shown in the chart below...
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Having said that, verapamil comes with some potentially disturbing side effects at higher dosages including heart blocks and arrhythmias that may require EKG monitoring. See the verapamil study by Dr. Peter Goadsby, M.D. et al. at
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I tried nearly every preventative listed in the cluster survey at the left when I was episodic... but when I looked carefully at the results, the risk-reward ratio was not in my favor with any of them including verapamil...
These preventatives were too invasive with too many side effects for me. In other words, I was taking some risks by using these preventatives, yet I was still having attacks... It just wasn't worth it...
The only preventative that worked... if you could call it that... was prednisone. I was on it for nearly 9 months for another condition and sailed through one spring cluster headache cycle with only a handful of minor attacks... but there was a price to pay... I became a refrigerator raptor and gained over 30 pounds in just a few weeks. On top of that, taking prednisone that long nearly destroyed my endocrine system... My doctors at NIH sent me to an endocrinologist who put me on a post menopausal regimen of fosamax and hormone replacement therapy for a year... That was clearly preferable to being chased down the street by sumo recruiters...
I turned chronic in 2005 when my spring cycle started and never ended... I wasn't officially diagnosed as chronic until early 2006. By then I was burned out on imitrex so my neurologists at NIH suggested neurontin (gabapentin)...
I gave the neurontin a month, titrating up to the maximum dosage the first week, but the resulting 3-martini buzz made driving unsafe and fat ankles caused by the neurontin required a diuretic. On top of that I was still having attacks... Again... Not worth it...
That put neurontin in with the other preventatives at the unfavorable end of the risk-reward ratio... so the doc's at NIH let me taper off the neurontin and on to oxygen therapy...
I'd done my homework here on CH.com, so made sure the Rx read 7 to 9 liters/minute with a non-rebreathing mask. Fortunately the home oxygen service delivered an M-size oxygen cylinder that same afternoon. It came with a flowmeter type oxygen regulator with a calibrated venturi tube and needle valve to adjust the flow like you see on the wall next to hospital beds.
My first attempt trying to abort a fast-rising Kip-7 attack was a total failure... 45 minutes after starting the oxygen the reservoir bag on the disposable NRB mask was constantly collapsed and the beast was still in control hammering out a solid Kip-8... so I took a 25 mg imitrex tablet, put an ice bag on my head... and kept on sucking...
When the pain finally subsided 30 minutes later, I got back on the Internet and found Dr. Todd Rozen's study on using oxygen therapy at 15 liters/minute...
When the next attack hit that same night, I jumped on the oxygen as soon as I felt the onset of the attack and cranked the needle valve open to 15 liters/minute... That flow rate worked... I got the abort, but it still took 30 minutes and I was still collapsing the reservoir bag with each breath...
That's when the light came on and the clue bird made a low pass... I had over 3000 flight hours flying Navy fighters and all of that flight time was spent breathing 100% oxygen... What was different? It was the flow rate... and I wasn't getting enough oxygen to ventilate my lungs even at a flow rate of 15 liters/minute!
At midnight when the third attack of the evening hit, I cranked the needle valve open to what I estimated was 30 liters/minute and was rewarded with an abort of a Kip-8 in 12 minutes... I'd broken the code... "More is better!"
By 06:00 the next morning I'd upped the flow rate to an estimated 45 liters/minute and was knocking down Kip-7s in 8 to 9 minutes...
From that point on, everything changed for me with respect to my cluster headaches... I was now in control... Although I couldn't prevent my attacks... I had the confidence of knowing I could abort them rapidly and reliably.
All the anxiety over the next attack was gone and best of all, the only cluster headache medication I've taken since then is an occasional snort of imitrex nasal spray during airline travel.
We've learned a lot since then about the respiratory physiology behind this very effective method of aborting cluster headaches... The most significant finding was the role played by CO2 levels...
We knew that oxygen was a vasoconstrictor and that breathing 100% oxygen at 15 liters/minue to push our system into hyperoxia would eventually abort our cluster headache attacks... most of the time... if we started early... and there were no other medical problems...
What we didn't realize until we reviewed several clinical studies, was that lowering CO2 levels and elevating arterial pH by hyperventilating with 100% oxygen until we achieved rerespiratory alkalosis enhanced vasoconstriction and the abortive effects of hyperoxia resulting in safe and very fast aborts of cluster headache attacks.
We also learned that elevated CO2 levels and low arterial pH (too much acid) had just the opposite effect. They acted as powerful vasodilators... so powerful that they can totally negate the effects of hyperoxia and prevent oxygen therapy from aborting our cluster headache attacks...
I can hear the wheels turning... How can CO2 levels rise while breathing 100% oxygen... The reason this can happen is relatively simple to explain...
Our bodies run like an engine (metabolism). We burn fuel (glucose) and oxygen from the air we breathe and that produces energy, heat, CO2 and water.
If we're sleeping or sitting motionless in front of the boobtube, the engine is at idle and our lungs are able to inhale oxygen and exhale CO2 at low respiration rates and tidal volumes to keep the CO2 levels normal.
Normal respiration rates run 12 to 18 breaths/minute. With an average tidal volume of a half liter of air inhaled with each breath, that works out to a minute volume range (the volume of air inhaled in one minute) of 6 to 9 liters just to maintain normal CO2 levels.
Now lets look at the average CH'er having an attack and trying to abort it with oxygen therapy at 15 liters/minute.
The first thing you notice is the level of physical activity... (the engine is no longer at idle...) Most of us rock back and forth hunched over our knees and bang on our heads or we stand dancing in little circles holding our heads while the reservoir on our disposable non-rebreathing mask is constantly collapsed...
This increased level of physical activity means we've stepped on the gas and are now burning fuel and oxygen at a faster rate...
We're also generating a lot more CO2 as a direct result of that increased physical activity... and at this level of physical activity, our bodies require a minute volume of 15 to 20 liters of lung ventilation just to keep CO2 levels in the normal range...
Now here's the problem that can stick us firmly between a rock and hard place... The oxygen regulator is set to 15 liters/minute and the non-rebreathing mask will only let us breathe what comes from that regulator... A minute volume of 15 liters...
If we're lucky, we'll have just enough lung ventilation to keep CO2 levels in the normal range and we'll eventually achieve an abort of the cluster headache attack with oxygen therapy...
Unfortunately for most of us, under these conditions our bodies are demanding a minute volume of lung ventilation greater than 15 minute liters (a flow rate greater than the 15 liters/minute we get through the non-rebreathing mask) just to keep CO2 levels in the normal range.
When that happens, the distance between the rock and hard place gets much smaller and the squeeze in on... Our CO2 levels began to rise above normal and at some point, this condition completely overrides and negates the benefits of hyperoxia... In short, we don't get the abort with oxygen therapy and the beast hammers on in complete control...
Knowledge is power... Once folks understand the mechanics and physiology behind this method of oxygen therapy... the answer is simple... Hyperventilating on 100% oxygen is very safe and very effective. Using a non-rebreathing oxygen mask with a 3-liter reservoir bag or a demand valve makes this method of oxygen therapy easier. Above all, we need an absolute minimum oxygen flow rate of 25 liters/minute if we really want fast and reliable aborts...
Hope this helps,
Take care,
V/R, Batch