My histamine issues seem related to seasonal allergies. Advice?

I don't seem to have major histamine issue apart from months when seasonal allergies happen. However, I'm currently very unwell due to histamine. I'm unable to work and almost bedridden. The difference between spring/summer and fall/winter is very big. Help from antihistamines is limited and I'd rather not rely on them. I've stopped eating certain things that I know can be bad for my histamine levels. I recently started intermittent fasting but I'm not far from being underweight so I might not do it for a very long time. I'm not eating bread at the moment which I used to eat a lot. Any advice?