"i tried viibryd after being on citalopram for a year and a half to see if it would be better. i had no problems transitioning but i gained about 10 pounds in the first weeks i was on it full dosage. i never fluctuate more than 1-2 lbs - have weighed the same for 10 years -- and despite eating less &amp; exercising twice as much i couldn&#039;t lose the weight. after ~2 months i switched back to citalopram &amp; lost all the weight in about 2 weeks. without going to the gym."