Hey Bejeeber,
Your observation that your chronic CH'er pal's Graves' disease may be playing a role his present out of control high CH cycle is likely spot on.
Graves' disease is an autoimmune disorder where the thyroid goes postal and starts pumping out far more thyroid hormone than normal. This in turn sends calcium homeostasis into a tailspin. As calcium homeostasis and vitamin D3 metabolism are closely linked, your chronic CH'er pal is also very likely vitamin D3 deficient unless he's been taking vitamin D3 supplements.
I'd suggest he bypass his neuro and headache specialist and instead make a beeline Monday morning straight to his endocrinologist or the physician treating his Grave's.
When he gets there he needs to ask for a complete set of labs (endocrine panel, chemistry panel and complete CBC). The most import labs are for his 25(OH)D, calcium, and parathyroid (PTH) serum levels.
I'll wager a Coke & candy bar his 25(OH)D serum level has tanked. In other words he is likely vitamin D3 insufficient (20 to 32 ng/mL) and more likely deficient (<20 ng/mL).
If this is the case, your pal needs to start vitamin D3 therapy asap... and I'd suggest the complete anti-inflammatory regimen with 10,000 IU/day (or more) vitamin D3 plus 2000 mg/day Omega 3 fish oil and all the vitamin D3 cofactors: magnesium, zinc, boron, vitamin K2 and vitamin A all at RDA.
If your pal is vitamin D3 insufficient/deficient, he starts the anti-inflammatory regimen and stays on it, I'll double down on the bet that his present CH high cycle subsides and the frequency of his CH drops.
I base this wager on the results of data I've collected from over 300 CH'ers here at CH.com (and at least 20 from the Clusterbuster forum), who posted they started the anti-inflammatory regimen and included results of their 25(OH)D labs. Of the 300 CH'ers, 240 or 80%, reported they've experienced a significant reduction in frequency, severity and duration of their CH. 78% reported they experienced a 24 hour pain free response, and over 60% reported they've remained essentially pain free.
The following chart developed by Dr. Robert Heaney, MD, illustrates the time course 25(OH)D serum concentration response to vitamin D3 dose. I've overlaid the 25(OH)D lab data and response to this regimen collected from posts here at CH.com as color bands on this chart.
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The actual 25(OH)D serum concentrations for a therapeutic response fall in a range of 60 to 110 ng/mL. That makes the mean value of 85 ng/mL as a good target 25(OH)D serum concentration for you pal to shoot for with his vitamin D3 therapy.
In the mean time, all the chronic cocktail and pred burst will do is treat the symptoms...
Take care and please keep us posted.
V/R, Batch