Hi
@Sasha-
I'm mostly echoing
@justy and
@Gingergrrl, but if it helps, MCAS medicines are what got me from daily horrible migraines and under100 lbs to a sustainable weight. Without medicine, I react badly to histamine, tyramine, and
other biogenic amines- you may be reacting to more than tyramine without realizing it. I think that's very common.
FWIW, I usually had reactions--terrible migraines, nausea, vomiting, dizziness--that didn't look like traditional anaphylaxis (to me) so I kept insisting that I didn't have any allergies. Only occasionally did I have hives, flushing, tongue swelling, etc. It was amazing when the medicines kicked in and I could eat a range of food again--I literally went years not being able to eat oh-so-many foods without getting terrible migraines. I just wrote to my neurologist to let him know that this approach has helped migraines more than anything else we've tried. Srsly.
As Justy pointed out, you need both H1 and H2 blockers. Beyond that, I think people tolerate or respond to different things differently. If it helps at all (ie if this applies to you) I have low stomach acid, so Zantac wasn't a good idea for the H2 blocker for me. Instead I take Singulair, an asthma medicine that is prescription. Quite a few H1 and H2 blockers are over the counter, which helps, but some of the other medicines, like singulair, and the gastrochrom Gingergrrl mentioned-it stabilizes mast cells-are prescription. Currently I take zyrtec, singulair, gastrochrom and allegra, and also take diamine oxidase supplements before meals that have anything histamine-heavy or otherwise challenging in them. Quite a mix for someone who "doesn't have allergies" .
I haven't had side effects, but Gingergrrl's example would definitely be one reason to talk to your GP first. Hope this helps-Good luck figuring out what to do! I have a paper on mast cell issues somewhere that is really helpful. If you'd like it just let me know and I'll PM it to you.
And
@Gingergrrl, more hugs
! I'm so sorry you've had such a hard time! And so glad the benadryl at least helped stabilize things enough to eat something.
Vasha
P.S. I had out-of-range levels of histamine in my blood, which is an unequivocal marker of MCAS, but often doesn't show up bc histamine's so volatile. So the researchers I read--e.g., Dr. Afrin- say it can be worth treating to see if it helps even without the blood markers.
P.P.S I guess I'm saying for me anti-histamines have definitely been a Good Thing. YMMV. ;-)