When my MCAS was very bad, I took Atarax as a rescue med and without it, am certain I would have had to use the EpiPen. Now I have not taken Atarax in about 10 months, except as a pre-med for IVIG, and at this point, am fairly certain I do not even need it for IVIG but continue just to be extra cautious. Have you tried Atarax for your skin rash? Am wondering if it would help?
Edit: My MCAS doc had me take Atarax b/c I do not do well with Benadryl.