I only started taking this a few days ago. I had been on Cymbalta and that did jothing for me except make me have lots of sweating. I feel a bit off taking this and I am dizzy. Have had a bit of a headache and upset stomach too. I am to take 150mg for 1-2 weeks then take 300mg from the on. Is that a normal dose? How long does this med take to start working?