"i tried cymbalta right after i gave birth and i noticed a difference within days. my.mood swings before my period get very bad and i thought the medicine wasn&#039;t working anymore so i switched to prozac. big.mistake. i couldn&#039;t get out of bed. i switched back to cymbalta and am on day 2 and feel good. never had side effects or anything like that. this has always been fast acting and an overall good medicaton for depression and my anxiety."