Wait, I think I know SIN-co-pee (?), but I've never been sure about the intestinal one, and since tinnitus affects me I'm invested in… TIN-it-us?

That or tin-EYE-tus are acceptable as far as I'm concerned

What about… DWAH-d'num?

That's how I've always said it, but most of the GI docs I worked with pronounced it duo-DEEN-num.

I am not in medicine but have a strong feel that it should *not* be tin-Ni-tus even though the double n indicates that the second syllables starts with an n and it carries the stress.