I've been on T3/T4, hydrocortisone, Valtrex, Valcyte, IVIG, medications, nutrients, and botanicals for MCAS, and IV rifampin, azithromycin and doxycycline. We're also looking at meds for hyperadrenergic POTS and possibly Rituximab (as I fit with the people they've seen respond).
I've had a trend of steady improvement over the past 8 months, though its cyclical due to the IVIG cycle. I had the best day in 2 1/2 years on Friday, where I was active most of the day and felt normal, though I still have crashes, but they're not as bad as they were.