I have had Fibromyalgia for many years now. I am always in pain, but I cope. I have been taking Effexor for years and it has worked well for depression. That is until about two months ago when it stopped working. I didn't want to get out of bed, I didn't want to get dressed, I cried, and I do not want to leave the house. My doctor put me on Lexapro 20 mg about 4 weeks ago. I am a little better, but not much. Is 4 weeks long enough or should I give the drug more time to get the full effect? Thanks for any input.