I used lexapro for four weeeks it gave me extremely bad headaches therefore my doctor switched to effexor and I used it for only two weeks due to it giving me terrible headaches also. I was on these meds for anxiety. I got a mri on advise from my doc because he believe the meds triggered something to cause the headaches. The mri was normal. The first three weeks I was off I got debilitating headaches and the next three weeks they decreased in pain some but I still have this numbness in my head like there is no blood flow and tightness in my chest. Could I still be having withdrawals of these meds after only taking for 6 weeks and being off them for 6weeks? Also, why did the meds cause these headaches and what can I do to help the withdrawal if it is withdrawal?