Good Day, Josie Sullivan! Citalopram is the generic name of Celexa, the trade name for an antidepressant (AD) drug of the SSRI class. You can read about it at PC or many other places on the Web.

Here's PC's general article on Antidepressant Medications.

Keep in mind that AD meds generally take some time (several weeks) to reach full effectiveness for most people. Also, because we're talking brain chemistry, effects can be highly individual. What works for one depressive may be totally wrong for another. Hopefully, you'll start to feel some relief soon. If not, don't give up. Keep track of suspected effects and side effects and inform your GP. You've got to work together as a team.

Best wishes for success!

PS: Gimmeice beat me to it...