Hi Marge, It's not in your head!  Antidepressants are associated with both weight gain and weight loss.  Sound strange?  Well, in some people they may increase or decrease your rate of metabolism without you changing your daily caloric intake. Another way antidepressants can cause weight gain is by causing hormonal changes that increase your appetite. From my reading, Celexa appears to be less associated with weight gain than some of the other SSRI's, but that doesn't mean it's not causing your weight gain.  One study indicated that Celexa has the potential to increase cravings for carbohydrates, for example. My advice would be to talk to your doctor and/or a nutritionist. They can help you figure out whether the citalopram (Celexa) is causing your weight gain and/or if there are other factors contributing to it.   Regards, Dr. Jennifer Fee www.drjenniferfee.com www.thestressmasters.com