I started 25mg of the generic Zoloft for 7 days, day 8 I doubled it to 50 and I think I had my first serious panic attack as I felt like I was having a heart attack for hours. I was afraid to go to sleep, so I called dr and she said to go down to 25, but back up to 50 the following day. I tried taking 25, but I felt just as bad as th previous night... so... Last night I chose to just not take it at all as I am scared of another attack, I had to call out of work and that sucked... My chest still seems tight but it's not anywhere as bad as the first attack, but has left me constantly afraid of the medicine. did any one have this happen? I was also really thirsty and chest seemed like it was burning.