Hey Akash,
Glad to hear you've found a cocktail of preventatives that work for you...
In analyzing the results of the cluster headache survey many of us took in 2008, the ongoing survey here on CH.com and reading posts on this topic over the last four years, it appears the most important factor in arriving at an effective preventative regimen for your cluster headache attacks is a neurologist who is willing to work with you in finding the magic combination that works...
It's equally important that your neurologist stays with you when that regimen's effectiveness wanes after time to find another as the beast is crafty in figuring ways around any one method of preventing it's unrelenting torment.
What flow rate are you using with your oxygen therapy and how long have you been using it? How long do you need to stay on oxygen to abort your attacks?
Re-attacks are common for the first month or two after starting oxygen therapy... We've defined a re-attack as another cluster headache that occurs between 15 to 45 minutes after a successful abort with oxygen therapy.
What appears to be happening is that oxygen therapy at higher flow rates is capable of aborting the pain of a cluster headache attack, but not the triggering mechanism if the abort time is short.
When the effects of hyperoxia (breathing 100% oxygen) and/or respiratory alkalosis (hyperventilating on 100% oxygen) dissipate... and the triggering mechanism is still active... and the cluster headache returns... we call this condition a "re-attack."
We also call them re-attacks as the term "rebound headache" only applies to a condition that arises if a headache medication has been overused to the point where the body develops a resistance to that medication and you need to take increased dosage to achieve a therapeutic result...
In short, and in order to place oxygen therapy in perspective with other headache medications... if you had a resistance to oxygen... you'd be pushing up grass rather than mowing it...
Fortunately, re-attacks are just another cluster headache that are easily aborted with oxygen therapy. Moreover, the frequency of re-attacks can be lowered by staying on oxygen after the abort by bringing the total oxygen time up to 15 minutes.
In other words, If it takes 6-7 minutes to abort an attack with oxygen therapy at a flow rate of 25 liters/minute and you are still experiencing re-attacks, lower the flow rate to a range of 9 to 12 liters/minute or what ever feels comfortable after the abort, and breath that flow rate for another 8 to 9 minutes to bring the total oxygen time up to 15 minutes.
We found the majority of aborts using an oxygen flow rate of 15 liters/minute to abort their attacks took longer than 15 minutes to achieve a pain free state and that when this occurred, the incidence of re-attacks was very low.
It's also been my experience, and that of several other long time CH'ers, that a high frequency of attacks a day can be an indication of a low arterial pH (too much acid).
This is frequently a result of diet and at times of the year, allergic or histamine reactions, but it can also occur with other co-morbid medical conditions that lower arterial pH.
When the frequency of my attacks go up in a "high cycle" I start pushing calcium citrate tablets with vitamin D, magnesium and zinc. I take three to four of these tablets a day along with Omega-3 gel caps and two or three glasses of lemonade.
The calcium citrate tablets and the citric acid in lemonade work as a buffer in the stomach to lower acid levels (elevate arterial pH) and that usually breaks the high cycle and I drop to 3 to 4 attacks a week. The Omega-3 aids in making calcium more available to the body.
I also cut back on red meat in favor of more cold water fish like wild salmon, halibut, and cod high in Omega-3 as well as a shift to poultry. I also eat a lot more more green veggies and snack on almonds. I'm not a vegan, but I'm sure your cardiologist would like to hear you're eating this kind of diet...
The following link provides an explanation of alkaline forming foods that can be eaten to bias arterial pH up to the high end of the 7.35 - 7.45 normal pH range. From my experience, it only takes a small shift to bring relief from a high cycle.
Many of these food types also aid in lowering inflammation that can also lead to an increase in the frequency of attacks.
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Note that a food's acid or alkaline-forming tendency in the body has nothing to do with the actual pH of the food itself. For example, lemons are very acidic, however the end-products they produce after digestion and assimilation are very alkaline so lemons are alkaline-forming in the body. Likewise, meat will test alkaline before digestion but it leaves very acidic residue in the body so, like nearly all animal products, meat is very acid-forming.
Take care and hope this helps,
V/R, Batch