"i have been on pristiq for 4 months now due to panic attacks and anxiety and after the first 3 weeks i saw great change, but a few weeks after that it seemed like it had just stopped working so my doctor doubled my dosage. now i&#039;m having nightmares. if i accidentally skip a dosage my head does this really weird thing and i just can&#039;t describe it. i am extremely irritable about every little thing or i&#039;m just really happy (up and down). i have no energy most days. i just want to stay in bed and do nothing. i&#039;m nauseated all the time. i&#039;ve actually lost about 20 pounds in 4 months bringing me down to 101 pounds. "