A number of side effects have been reported with Celexa, and weight change is considered a common side effect. In clinical studies, weight gain was reported as a frequent side effect of this medication, occurring in more than 1 percent of people, although the exact percentage was not reported.
Weight loss was also reported in more than 1 percent of people (again, the exact percentage was not reported). On average, people lost only about a pound while taking Celexa. However, it is possible for people to lose large amounts of weight while taking the medication.
If you are taking Celexa and weight change occurs, talk to your healthcare provider. He or she may perform a physical exam to look for other causes of weight gain or loss, such as certain types of medical conditions. If the problem continues, your healthcare provider may recommend lifestyle changes or a possible switch to another antidepressant.