| Celexa (citalopram hydrobromide): Drug Safety Communication - Abnormal Heart Rhythms Associated With High Doses
AUDIENCE: Psychiatry, Cardiology
FDA notified healthcare professionals and patients that the antidepressant Celexa (citalopram hydrobromide) should no longer be used at doses greater than 40 mg per day because it can cause abnormal changes in the electrical activity of the heart. Changes in the electrical activity of the heart (prolongation of the QT interval of the electrocardiogram [ECG]) can lead to an abnormal heart rhythm (including Torsade de Pointes), which can be fatal. Patients at particular risk for developing prolongation of the QT interval include those with underlying heart conditions and those who are predisposed to low levels of potassium and magnesium in the blood.
Studies did not show a benefit in the treatment of depression at doses higher than 40 mg per day. Previously, the citalopram drug label stated that certain patients may require a dose of 60 mg per day. The citalopram drug label has been revised to include the new drug dosage and usage recommendations, as well as information about the potential for QT interval prolongation and Torsade de Pointes. See the FDA Drug Safety Communication Data Summary for additional information.
BACKGROUND: Celexa (citalopram hydrobromide) is in a class of antidepressants called selective serotonin reuptake inhibitors (SSRIs).
RECOMMENDATION: Citalopram causes dose-dependent QT interval prolongation. Citalopram should no longer be prescribed at doses greater than 40 mg per day. Citalopram should not be used in patients with congenital long QT syndrome. Patients with congestive heart failure, bradyarrhythmias, or predisposition to hypokalemia or hypomagnesemia because of concomitant illness or drugs, are at higher risk of developing Torsade de Pointes. See the FDA Drug Safety Communication for additional recommendations for healthcare professionals and patients.
Healthcare professionals and patients are encouraged to report adverse events or side effects related to the use of these products to the FDA's MedWatch Safety Information and Adverse Event Reporting Program:
* Complete and submit the report Online: www.fda.gov/MedWatch/report.htm
* Download form or call 1-800-332-1088 to request a reporting form, then complete and return to the address on the pre-addressed form, or submit by fax to 1-800-FDA-0178
Read the MedWatch safety alert, including a link to the FDA Drug Safety Communication, at:
http://www.fda.gov/Safety/MedWatch/SafetyInformation/SafetyAlertsforHuma...
FDA提醒醫護人員及病人，一種SSRI的抗憂鬱劑Celexa （citalopram hydrobromide）使用劑量不應高於40 mg/day，因為有可能會引起心臟電位不正常（QT interval prolongation）而導致心律不整（包括Torsade de Pointes），嚴重時可能致死。有可能發生QT interval prolongation的病人包括，本身有心臟疾病及本身有低血鉀及低血鎂的病人。
研究結果並無顯示使用Celexa超過40 mg/day有任何益處。Citalopram的舊仿單說明某些病人可能需要用60 mg/day治療，現在已修訂新的建議劑量及關於QT interval prolongation及Torsade de Pointes的資訊。
Citalopram會引起與劑量相關的QT interval prolongation，故劑量不應超過40 mg/day，且不可用於有先天性long QT症狀的病人。病人因為疾病或藥物而有心衰竭、心律過慢、低血鉀或低血鎂時，都是引發Torsade de Pointes的高危險群。其它資訊及建議請見網站上Drug Safety Communication Data Summary。
相關訊息與連結請參考FDA網址：http://www.fda.gov/Safety/MedWatch/SafetyInformation /SafetyAlertsforHumanMedicalProducts/ucm269481.htm
[Posted 08/24/2011]
資料來源：美國FDA之藥物安全警訊
資料提供：台大醫院藥劑部 |
資料來源：藥師週刊（第1741期）