Hey Ernst,
Welcome aboard CH.com and welcome to the anti-inflammatory regimen. I'm sorry I didn't see your post earlier as I would have suggested you ask your PCP/neurologist for the lab test for 25(OH)D. This is the serum level metabolite of vitamin D3 that's used to measure its status.
Not knowing your serum concentration of 25(OH)D makes it difficult to predict how long it will take for you to experience a favorable response with a cessation of your cluster headaches... or at least a significant (~80%) decrease in the frequency, severity and duration of your CH.
If you didn't get this lab test today, be sure to call your PCP/neurologist and ask him or her to call in a script to the nearest diagnostic lab. There are several located throughout the UK
The erratic nature of you CH symptoms is not uncommon... Several CH'ers have reported similar patterns after starting this regimen. Nearly all of them stuck with the regimen and experienced a favorable response when their 25(OH)D serum concentrations climbed into the "Green Zone" 60 to 110 ng/mL, (150 to 275 nmol/L for you in the UK).
At 30,000 IU/day vitamin D3 and assuming your 25(OH)D serum concentration was a little less than 75 nmol/L at start of this therapy, it should take a week to 10 days for a more favorable response to this regimen.
As long as you're otherwise healthy with no other comorbid medical conditions involving your liver, kidneys, thyroid, parathyroids, or pancreas... part of the erratic nature of your CH symptoms may be due to a low arterial/systemic pH... Too much acid.
It doesn't take too much of a downward shift in pH to the lower end of the normal reference range of 7.35 to 7.46 to trigger vasodilation... The lower the pH, the greater the vasodilation and that makes just about any cluster headache treatment less effective.
If you're getting hit while sleeping... the odds are high this is due to a low arterial pH. This is due to the low respiration rate while sleeping where your arterial oxygen partial pressure is lowest and your CO2 partial pressure is highest. In short, a prefect storm with a high probability to trigger a cluster headache.
Under these conditions, the body's homeostatic processes that control arterial pH kick in and they signal your arterioles and capillaries to dilate, your heart to beat faster and your lungs to increase the respiration rate. You body does this to increase the flow of CO2 to the lungs where it's exhaled.
The easy way to test for a low arterial/systemic pH is by taking Alka-Seltzer tablets in water a couple times a day or a sodium bicarbonate tonic... i.e. a half teaspoon of baking soda in 4 ounces of water four times a day (two hours after eating and right before going to bed).
If either of these two methods result in a drop in the frequency, severity and duration of your CH... you'll need a longer term solution by eating an alkalizing/GOMBS diet.
GOMBS = Greens, Onions, Mushrooms, Beans/Berries and Seeds... a handful of each a day will do. You can find info on a GOMBS diet at the following link:
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I didn't see any mention of oxygen therapy... Even the 15 liters/minute prescribed there in the UK can make a significant difference in the duration of your cluster headaches.
I've attached the HOOF form used there in the UK. Fill it out and take to your PCP/Neurologist to speed up the process of obtaining home oxygen therapy for your CH.
Take care, thanks again for the post, and please keep us posted on your progress with this regimen.
V/R, Batch