Well, black might be overstating it, but gray/black and only (so far) on the right upper portion. Just noticed it last night when brushing his teeth. Eight days into rad tx. He's not up yet this a.m. but I see he was up middle of the night as there's the bottle of Compazine, Pepto-Bismol, crackers, water, and a book here downstairs. I typed in "black tongue" under "Search" but didn't see anything regarding this weird-looking condition (which he only noticed b/c he was checking his oral cavity w/a light last night, not b/c it hurt or anything. Anyone else have this? Is it likely fungus (without the fun)?

I had it.
I think they called it hairy tongue.

Then I had Thrush. As best I recall both can be due to antibotics, reduced saliva, yeast infection.... all that bad Rad stuff!

It is benign, but as best I recall the Thrush meds (Nystatin)took care of it.

Is the gray in the middle of his tongue mostly? That's where mine is usually at. That part is the tomgue muscle if it is, I have to brush that at least 2 times a day and it helps. I guess it's from having the sides removed during surgery and the muscle just stands up and can be noticed. Just like a big bump in the road, you have to respect it and brush.