I have both good and bad experience of effexor. I was really helped by effexor in the beginning. I was on it for three years . In the start it was a really good thing and it cured my depression ( I was suicidal) but after I while it was a lot of unacceptable side effects that at last made me quit. It was nightmares, bad sleep, I was losing weight and had no good results when I went out running (the med made me in some strange way more slow ?!!) and worst of all was that I started to bleed between periods. All this things stopped when I quitted taking effexor so I am almost sure it had to do with it.