Over The Counter meds that help?

Alongside bloodwork based recs from my doc. I started talking Certrazine HCL 10mg daily a couple months ago, and it's caused some symptom ease. I know it's a histamine/MCAS thing moreso. I'm seeing specialists and having tests. It's been 5 years. I looked over some of the resources provided (shout out Mods! thank you!) and it seems most of what benefits us must be prescribed to have access. Anyone have anything OTC help? I'm in talks consistently with my doc about treatment and currently in a waiting season.