My experience may be interesting for people who have not been able (yet) to get the D3 regimen work for them or who are trying it in combination while still on Verapamil.

After two unsuccessful attempts with a relatively aggressive D3 dosing schedule I made my third attempt a few months ago.

I am chronic and after alternating between Lithium and Verapamil over the past few years (and a dozen other things) I had to conclude that even in low cycle the only thing working reasonably well was Verapamil at 680-720mg per day.

While on this Verapamil dose I started with the following daily regimen

10,000 IU Vit D3
Omega 3 (EPA 360mg / DHA 240mg)
500mg Magnesium
10 mg Zinc

Daily with the biggest meal and glass of fresh orange juice.

Didn't use any calcium because of Verapamil or Vit K (had a thrombosis last year) and also didn't apply any Vit D3 loading doses, sticking to only 10,000 per day.

After 3-4 weeks on this dosing schedule I started reducing Verapamil by 40mg per week. Interestingly, for 1-2 days after each weekly Verapamil reduction I felt the occasional pressure in my CH area that then settled.

I am now down to 160mg Verapamil (which I know would do shit for my CH on its own) on the same D3 dosing schedule and my head is holding up.

Since I haven't been on this low dosage of prevents for many years I am now certain that the D3 regimes is/has taken over.

Slow in and slow out I believe were the keys to making it work thus far in my case.

Neuropath, I wish you the best of luck with this and will be following your progress closely.