Were you still under effect of Fixer when you talked to him?
No. My addiction never came back. Add to that I have gotten addicted at least two more times since, and Fixer again did the trick.
I could complain that this "makes it too easy" but really I kind of like it. Traveling clear across the map (I'm not a big fast travel guy) to go see a doctor is less of a "challenge" and more of an annoying chore.
That said if the bug (?) gets fixed, my glass will
still be half full because I'll just play the "immersive" card.