Really glad I found this post, good to have others who know what I've ben dealing with.... and really depressing to know how seemingly common this has been!!

Same symptoms. ~1 week after my 3rd Moderna shot February 2022, I broke out in full hives and severe allergic reaction. Went to urgent care and received several steroid shots/pills. The severe reaction went down, though I've been dealing with moderate to severe dermatographia and chest tightness since then. I have been taking Zyrtec and Benadryl on and off, which seems to help a bit but not 100%. I'm currently on day 5 of no antihistamines and have been feeling absolutely miserable. Skin marking and chest tightness is about the same, but the itchiness is unbearable. It is extremely sensitive, and the itching is deep and painful. I have zero history of allergies, and was hoping this would go away on its own. 4 months later and those hopes are disappearing.... Really praying for a treatment for this. Stay strong, my Etch a Sketch-skinned comrades.