They shouldn't raise your blood sugar if that's what you're asking. However, I'd strongly advise limiting yourself to 1 or 2 of these.
I bought a bag shortly after I was diagnosed thinking I could eat as many as I wanted....eating about 10 of them at once did not go so well for me.
I won't get into specifics, but Werther's have sugar alcohols in them which can seriously upset your stomach when consumed in large quantities.
Side note: I have a very strong stomach and not a lot upsets it. However, Werther's are one of the few things I avoid completely these days.