Bhsloane -
Clearly your reactions to the vaccines falls into the allergy category. And the use of an antihistamine med has worked well for you.

That said I do have a suggestion about its continued use, if I may.

I too have a long history of high histamine levels. But mine are more in the genetic autoimmune category and caused by Celiac Disease.

My suggestion is actually a caution. Not that you will over use the antihistamine med - rather that by stopping its use prematurely you may eventually develop Adrenal fatigue (AF) and additional symptoms related to AF.

What is Adrenal Fatigue and why does it happen? AF is a condition where persistent high levels of histamine overwhelm your Adrenal glands ability to create 2 important hormones - cortisol the body’s primary anti-inflammation hormone and Aldosterone the body’s way of both maintaining water content by controlling Sodium and maintaining enough Sodium needed for proper nerve function.

Your high histamine is caused by an immune reaction to the vaccines, while mine was to gluten. The causes are different but the results can be similar.

You can continue to monitor your med use and only take the med when you sense the allergy symptoms. Or you might monitor your body’s CRP levels with periodic blood tests. CRP or C-reactive protein is an indicator of a body’s inflammation. And luckily it is treatable with injections of vitamin B12.

Why CRP? Your body’s immune system is under constant attack from minor dings, food reactions, insect bites, etc. That’s its job!

But we often don’t feel the inflammatory histamine levels that these minor attacks cause, because we all have thresholds that if exceeded we will feel or if not exceeded we don’t feel.
Either way, higher than normal histamine levels near your reactive threshold could possibly lead to AF over time.

Basically your antihistamine meds are a supplement to the body’s normally produced antihistamine called DAO. The bulk of DAO is produced in your intestines so as long as you do not have any gut issues the DAO should suffice. But any gut issues that interfere with its production can trigger the return of symptoms.

Clearly the causes of FA can be complex, but as long as the vaccines continue to cause any immune system reactions periodic use of your med could help limit the potential for developing FA and the cascade of other related symptoms.

I sincerely hope that your allergic symptoms do not return and that the immune responses to the vaccines eventually disappear. But, by monitoring your CRP is a good way to find out.
Chris47 -