G'Day Engels,
As Colin pointed out, your 25(OH)D is spot on in the middle of the green zone at 205 nmol/L. What I suspect may be happening is you've a sub-clinical allergic reaction that's been running for some time...
By sub-clinical, I'm saying no outward or obvious allergy symptoms... Just because you haven't noticed them doesn't mean they're not there. Even people who are relatively immune to allergies still experience them albeit at a low or sub-clinical level.
During an allergic reaction i.e., inflammation, mast cells (part of the immune system) in the skin, lining the nasal passages, lungs and GI tract start releasing histamines.
During typical allergic rhinitis, also known as hay fever or pollinosis, our immune system overreacts to allergens such as pollen, mold spores or other chemical toxins and we experience a runny or stuffy nose, sneezing, red, itchy, and watery eyes, and swelling around the eyes. Guess what... The brain is suffering from a similar inflammation during an allergic reaction except it's called neurogenic inflammation.
Here is where an allergic reaction hits cluster headache sufferers the hardest... When neurons within the hypothalamus and trigeminal ganglia are insulted by histamine from an allergic reaction, they trigger the release of calcitonin gene-related peptide (CGRP) and Substance P. Both are key parts of the cluster headache pathogenesis. CGRP triggers rapid neurogenic inflammation and severe pain.
The term ‘neurogenic inflammation’ has been adopted to describe the local release of inflammatory mediators, such as substance P and CGRP, from neurons. Once released, these neuropeptides induce the release of histamine from adjacent mast cells. In turn, histamine evokes the release of substance P and CGRP; thus, a bidirectional link between histamine and neuropeptides in neurogenic inflammation is established.
What all this means is a simple allergic reaction can trigger a chain reaction and self-sustaining perfect storm within the brain producing more CGRP and Substance P than can be down-regulated or suppressed by vitamin D3... hence no response or at best, only a limited response to the anti-inflammatory regimen. In other words a CH'er suffering from an allergy whether obvious or sub-clinical (no outward or obvious symptoms) becomes refractory to the anti-inflammatory regimen's capacity to prevent CH...
This same mechanism likely accounts for the CH'er being refractory to most other CH prophylaxis and likely makes oxygen therapy less effective with longer abort times.
Fortunately, I stumbled across a solution for this self-sustaining perfect storm last March during a very heavy pollen fall from Alder and Big Leaf Maple trees that coated my black pickup truck turning it gray.
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Within hours of the pollen fall starting... it looked more like a bad dust storm, I began to experience symptoms typical of allergic rhinitis... A few hours later during a nap, the CH beast jumped ugly. I aborted same with hyperventilation and oxygen therapy, but was concerned like you, that 10,000 IU/day vitamin D3 wasn't sufficient during an allergic reaction...
I began loading vitamin D3 at 50,000 IU/day (chewing the softgels and swirling the contents under my tongue and holding them there for 5 minutes... i.e., sublingual). I also doubled my magnesium intake to 800 mg/day... After three days on this dosing schedule, the CH beast was still jumping ugly 3 to 4 times a night.
Now you need to understand... that as the guy who developed the anti-inflammatory regimen in October of 2010 and who had remained pain free ever since
(with the exception of a couple 25(OH)D burn down tests a year where I intentionally stopped taking the entire regimen until I got hit...) getting hit like this was a wake-up call...
About that time the clue bird made a low pass and my Good Idea light came on bright and flashing... TREAT THE ALLERGY !!!
After a few hours researching the pathogenesis of allergic rhinitis and available antihistamines, I selected Benadryl (Diphenhydramine), a first-generation antihistamine that passes through the blood brain barrier to block H1 histamine receptors in neurons throughout the brain and in particular, the hypothalamus and trigeminal ganglia where production of CGRP and Substance P are highest. Second- and third-generation antihistamines, the "non drowsy" type, cannot do this so will not be effective in blocking the histamine receptors in neurons throughout the brain.
I started dosing at 25 mg Benadryl (Diphenhydramine) four times a day. Within 3 to 4 hours, my allergy symptoms began to subside. Within 12 hours, the CH beast was nowhere to be found and I was back CH pain free.
After a few days on this dosing schedule, I reduced my vitamin D3 intake down to 20,000 IU/day and the Benadryl (Diphenhydrmine) down to a 25 mg tablet twice a day. I stayed on this dosing schedule until the pollen fall was over... ~ another 2 weeks, then dropped my vitamin D3 intake back down to the 10,000 IU/day maintenance dose and stopped the Benadryl (Diphenhydramine).
So there you have it... The likely reason you've not responded to this regimen and the same reason many of the other 18% of CH'ers don't respond to it either. As a side note, I've had several of the anti-inflammatory regimen "non responders" and partial responders, start a course of Benadryl (Diphenhydramine) at 25 mg twice a day and report they are now experiencing a pain free response.
There are a few other anti-inflammatory and immune system helpers you can try. A 1,000 mg tablet of vitamin C taken five to six times a day (every two hours) will help jazz up your immune system and also help quell inflammation.
Why vitamin C? Vitamin C, also known as ascorbic acid, is a water-soluble vitamin. Unlike most mammals and other animals, humans do not have the ability to make ascorbic acid and must obtain vitamin C from the diet.
Vitamin C is very safe... However, like magnesium, if you take too much... you'll get loose as a goose...
Dr. Linus Pauling used to take 19,000 to 20,000 mg of vitamin C a day... He had lots of critics when he suggested vitamin C doses like this... but then he had two more Nobel prizes than any of his critics and had outlived most of them when he passing away at the age of 91...
You can read about the Linus Pauling therapy at the following link:
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The Linus Pauling Institute Micronutrient Information Center at Oregon State University has a very informative section on Vitamin C at the following link:
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"Although the upper intake level (UL) for vitamin C is 2000 mg/day, there is no reliable scientific evidence that large amounts of vitamin C (up to 10 grams/day in adults) are toxic or detrimental to health."
Like vitamin D3 and the prevention of rickets, the amount of vitamin C required to help prevent chronic disease is higher than the amount required for prevention of scurvy.
If you're like me, and read through the entire fascinating link on vitamin C and what it can do for you healthwise, you'll run to check the medicine cabinet... and if there's none there, you'll pick some up at the next opportunity..
Curcumin (Turmeric) is another anti-inflammatory. 400 mg/day should be sufficient. Just be sure to take it on a full stomach as 400 mg is equivalent to the amount of turmeric you get 3 or 4 curry dinners...
I realize this is a long read... but I hope this helps. Just make sure you keep your PCP or neurologist in the loop when taking anything new...
Take care and please keep us posted.
V/R, Batch