I had allergy tests done two weeks ago and was positive for everything. The nurse then tested for glycerin, and I was positive for that, also. Glycerin is the preservative used in the test samples, so that is why I showed positive for everything. Because allergy to glycerin is rare, I have been unable to find an allergy practice in my city that treats it, or even has any advice about it. I contacted the allergy/asthma specialists part of the AMA and was told that calling Duke Medical Center or another research facility might be a good idea. I just may do that. I am immunosuppressed and have a number of other medical issues, so I really want a simple way to deal with this new issue!