LETTER
Prescribe Escitalopram Instead of Citalopram To the Editor: I would like to respond to the recently published review entitled “Citalopram, QTc Interval Prolongation, and Torsade de Pointes. How Should We Apply the Recent FDA Ruling?”1 A revised Drug Safety Communication on Celexa was posted on the US Food and Drug Administration (FDA) Web site on March 28, 2012, which included data obtained from randomized double-blind placebo-controlled crossover studies of the effects of citalopram and escitalopram on the corrected QT [QTc] intervals in adults.2 Citalopram 20 mg caused an average QTc prolongation of 8.5 ms (95% confidence interval [CI], 6.2-10.8 ms), while the therapeutically equivalent dose of escitalopram (10 mg) prolonged QTc by an average of only 4.5 ms (95% CI, 2.5-6.4 ms). Similarly, citalopram 60 mg prolonged QTc by 18.5 ms (95% CI, 16.0-21.0 ms), while the therapeutically equivalent dose of escitalopram (30 mg) prolonged QTc by only 10.7 ms (95% CI, 8.7-12.7 ms). These data demonstrate that the harmful effect on QTc interval prolongation is nearly double for each dose of citalopram compared with its therapeutically equivalent dose of escitalopram. It is known that only the S isomer of citalopram (escitalopram) has antideFunding: None. Conflict of Interest: None. Authorship: The author had access to all of the data and is solely responsible for writing this manuscript.
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pressant effects; so, while the R isomer of citalopram confers no antidepressant benefit, it does cause a harmful effect on QTc prolongation roughly equivalent to that of the S isomer. In addition, the widely used over-the-counter antacid omeprazole has a major interaction with citalopram that further increases prolongation of the QTc.3 Newly available generic versions of escitalopram should reduce its price substantially, eliminating the last compelling reason for clinicians to prescribe citalopram at all. It seems prudent to transition all patients who are currently taking citalopram to the equivalent dose of escitalopram at the earliest opportunity. David L. Keller, MD, MS Providence Medical Group Torrance, Calif
http://dx.doi.org/10.1016/j.amjmed.2012.10.024
References 1. Vieweg WV, Hasnain M, Howland RH, et al. Citalopram, QTc interval prolongation, and torsade de pointes. How should we apply the recent FDA ruling? Am J Med. 2012;125(9):859-868. 2. U. S. Food and Drug Administration. FDA Drug Safety Communication: Revised recommendations for Celexa (citalopram hydrobromide) related to a potential risk of abnormal heart rhythms with high doses [August 24, 2011, revised March 28, 2012]. Available at: http:// www.fda.gov/Drugs/DrugSafety/ucm297391.htm. Accessed September 10, 2012. 3. Drugs.com. Drug interactions between Celexa and omeprazole. Available at: http://www.drugs.com/drug-interactions/celexa-with-omeprazole679-335-1750-0.html. Accessed October 4, 2012.