"i have been on pristiq for 4 months now. having never been treated for any kind of depression or mood disorder i wasn&#039;t sure what to expect.  the first 2 months i was at 50mg, had few side effects of headache and nausea but those subsided and i was generally feeling just not happy.. not sad. i asked my doctor to try 100mg and she agreed to go for it. now 2 months later on the 100mg i feel great!  no real side effects with the exception of hot flashes and sweats now and then, but nothing too uncomfortable.  i think the difference is higher dosage being more effective in my case is because i am overweight to begin with.  i am down about 12 pounds now and blood pressure is holding steady (132/82) too."