Welcome to the forum, @Idnam! Ranitidine and Famotidine are not proton pump inhibitors. They are H2 blockers. It is true that histamine intolerance is common in the celiac population. We often don't produce enough of a histamine regulator called DAO (diamine oxidase). Not sure, but this may be due to damage to the gut lining by celiac inflammation. You might also want to research MCAS (Mast Cell Activation Syndrome) as it is often goes hand in glove with histamine intolerance and is actually the root cause. Or, at least that is my understanding. By the way, you can purchase DAO capsules but there is not clear evidence they work.

Very interesting, @Idnam.  When I was experiencing this problem at its worse, I found high carb meals like lots of rice or too many cookies were a trigger.

Really interesting, Kitty, thank you. 

Thankyou I will definitely have a look your very  insightful and a lot is making sence 👍

Oh my, I have always had the symptoms for B12 deficiency, which is why I had the blood test that led to my celiac disease diagnosis I had been taking  B vits have been always been amazed that all ,my bloods were perfectly normal! I queried this many times with my doctor as to whether the B12 was active and being absorbed or whether it was just in my bloodstream. They dismissed this idea. And of course I still take them. Thank you so much, what a revelation and really quite understandable,  I am about due for my annual full blood test so maybe I will just stop taking them?