Usually by 6 weeks the medication is working to full effect.
If your still not feeling any better I would call your doctor.
I was on effexor for 5 years and it sounds like your not on the right medication. I had the same effects and came off of effexor XR becuase of it. There lies another problem. Coming off of effexor XR is pretty rough. I have posted on it in the forums. Effexor is one drug that I would really look into before staying on it. I am not a Dr and not telling you what to do but if it were me and I were feeling like you are I would goto my DR. immediately and tell him how it was making me feel.
You're getting the best of the effects by six weeks, if you are definitely taking it regularly. You may need a higher or lower dosage to work neurotransmitters differently, Effexor works on Serotonin and Norepinephrine and different doses make it play differently with chemicals.
TALK TO YOU DOCTOR!!!
If you have a good doctor, he or she will help you fix the drugs by this point.
I took a full 6 weeks and possibly a bit longer to even start to feel a response. It is the best one I've used though as it brought me back from the brink.
My feeling is your dose may be too low but without knowing more about you that's a wild guess. I needed to go to 550 mgs eventually before it stopped working but I responded at 300 mgs initially. I was pretty far gone though.
I've been on and off effexor since 2001. Now I take 150 mg. I started on 75mg and slowly went to 150mg. I would have to say at 150mg I have the fewest bouts of depression and more energy and motivation to go out and do things. You may need a higher dose, maybe go up another 75mg to 225mg. Do you mean up and down like mood swings? If this is true you might need a mood stabilizer in addition to an antidepressant. Hang in there.
I used to take Effexor for about 4 years. It took 300Mgs a day to give me any relief from my depression and anxiety.
Maybe your on too low of a dosage. Then again maybe Effexor just isn't the right medication for you.
I also have tried getting off effexor, it is sooo hard . Try to avoid starting it if possible.
Ask Dr. to try something else. Good luck.