Is this more or less complete symptoms list? Any hypersensitivity-like symptoms, or cutaneous ones exacerbated by QACs and other pesticides or odour neutralisers? I have someone who mentioned MCAS in her son and seemingly successful outcome. However, that guy had distinctive skin symptoms and it was very pre-pandemic. OTOH there is a minor study about H1 and H2 receptor blockers, but it was minor (sample + blind 50-60 individuals AFAIR) based on self-reporting. That's off the top of my head, I'm sorry for inaccuracies.