Citalopram is an antidepressant used to treat depression and anxiety. It is an SSRI (Selective Serotonin Reuptake Inhibitor), which means that it works by increasing the level of serotonin in the brain. It comes in the form of tablets, or as liquid drops that you put in a glass of water. It is only available on prescription. Citalopram is the generic name for this drug. It is also sold under the brand name Cipramil in the UK and Celexa in the US.