Thanks guys for being so supportive. I have proven to them that it is in fact the TOBI. I have stopped and started several times with the same results. This last time, I was off of it for 6 weeks, and 1 hour after the first treatment, it happened. During that time, I had been on a course of IVs to help with any possible infection. It seems that I have a blood vessel that just opens up when it sees TOBI (it happens in the same spot every time). Why this never happened before is a mystery.
I typically alternate months between TOBI and Colisten, so I would imagine they'll just have me stick with the Colisten for now. The problem is that I respond much better to TOBI, so losing it is going to be a problem. Maybe I'll ask about hypertonic saline when I go in.