Pulling this old topic out of the closet. It's a good topic for discussion.
There is plenty of research showing how histamine can play a role in cluster headaches. The Diamond Headache Clinic has for decades used a histamine desensitivevation (sp) program in their in-patient unit. It's a long process but many people have had good results in breaking cycles this way. (as well as plenty of failures along the way)
Many of us prior to getting a proper diagnosis rely upon OTC antihistamines that do provide some relief. You end up needing more and more. In todays world, I'd probably be investigated for having a meth lab with all the OTC antihistamines I used for my clusters. ( the first 4 years i had a "sinus infection")
Anyway, I was sent this recent article about histamines that I thought someone may find helpful. (Ignore the ads for wine ;-) https://drinkpurewine.com/blogs/histamine-intolerance-side-effects/histamine-intolerance
I hope everyone is having a great fall, at least weather-wise if not other areas of life.
Hang in there people,
Bob