"i have been taking lexapro for more than four years at 10mg-20mg.  it has been great at reducing mood swings, anxiety, and sadness. i have not noticed reduced effectiveness, however, my doc did move me up to 20mg because i was still experiencing pms mood swings and irritability.  i also have mild to severe depression.  there are only 3 side effects i have experienced and that is reduced libido, yawning, and inorgasmia. which i feel i can handle as long as i&#039;m happy and positive. i had tried zoloft before and it didn&#039;t make me happier it just made me jittery and jumpy all the time and i couldn&#039;t relax.  so, lexapro has definitely been the answer for me."