Hello Dr. Nagler, It seems that some of us with loud, persistent T experience low T days. I was wondering if you know what causes this to happen. There is no rhyme or reason to it. At first I thought it was the Xanax that I take but then wouldn't it be low everyday? It gets so low that it's just barely a squeal and on two occasions it disappeared completely. Sleep always brings it back. I used to be terribly disappointed that it came back --then I was thankful for the respite--lately it's getting so it doesn't seem to make much difference to my day either way. Could it be our brains trying to heal? I'm so sorry I couldn't get to Ewing to see you!