OMG yes it is awful. I couldn't take it and all the Antihistamines in the world were not helping.
So I went back to taking the histamine digestive enzyme.
I only know of 2 that don't have lots of extra stuff in them that may contribute to the problem.
just diamine oxydase
Histame works well and has some vit C and calcium
and DOAsin acailable through Swanson which has a lot of preservative.
I prefer the Histame but it is very expensive. Average is about one dollar per pill and I take 3 with each meal or snack. I eat ONLY low histamine foods but the itching keeps coming back.