I had used zoloft 25 mg last year for 10 months. I had common withdrawal effect as electric shock sensations accompanied with buzzing noise in head. But i also had experienced the same sensations in the first day i took zoloft 25mg in the evening when i was falling asleep. That day i was sleepless and had very fast heartbeat. I wonder: why i had experienced withdrawal effects about three hours later i took the first pill of zoloft? I wonder because i am seeking the culprit of my high frequency hearing loss and tinnitus occured and progressed after beginning of zoloft.