TWO anti-depressant drugs, Lexapro (Escitalopram) and Celexa (Citalopram), are close 'relatives' in terms of their chemistry and a comparison between their respective efficacies would therefore be interesting. Lexapro is the newest member of the SSRI family of drugs and Celexa could be considered its precursor.

The difference between Lexapro and Celexa is essentially a difference in their chemical composition. Celexa is a combination of two equal parts known as S- and R-enantiomer. However, R-enantiomer was found to be of no use in the anti-depressant role of Celexa, it was removed from the combination, leaving only the S-enantiomer/S-isomer. This split led to the formulation of Lexapro, the newest member of the SSRI family of drugs.

The advantages of Lexapro over Celexa are as follows:

Lexapro is more potent. The minimum daily dosage of Lexapro recommended is only 10-20mg compared to 20-40mg of Celexa.
Lexapro’s therapeutic action too is faster (less than two weeks) than Celexa.
Though the healing effect of both the drugs (in their respective dosages) is similar in the initial stages, Lexapro displays relatively better results in the longer term, i.e., after about 24 weeks.
As for safety, both Lexapro and Celexa have been seen to be equally safe and acceptable to the body system. Adverse side-effects from both the drugs were similar in nature and intensity, and they include: insomnia, anorgasmia, constipation, loss of libido, ejaculation problems, diarrhea, upper respiratory tract infection, among others. Withdrawal symptoms too are less with Lexapro than Celexa. Despite the demonstrated superiority of Lexapro, doctors often prescribe Celexa first because of its lower potency, and prescribe Lexapro only if the symptoms of depression or anxiety are severe enough to justify the strong-action Lexapro.