I have panic syndrome (panic attacks), and I feel the condition was greatly exacerbated, if not caused, by smoking marijuana in college. Of course, back in those days, who knows what it was laced with.
Anyway, I don't have much doubt about that because the first and worst panic attack I ever had was while smoking marijuana. After that I would have them any time, even when not smoking marijuana.
As I've gotten older, and more years pile up since the last time I smoke marijuana, the panic attacks have become more controllable, but still with me. If I had known this, I would never have smoked pot. But everybody said it was cool and I was young and stupid.
I've actually read some literature that supports this, also.
In the end, I'm better off without pot, or booze for that matter. Just high on life. : ) I won't even take cold medicine.