FDA Drug Podcast for Healthcare Professionals: Abnormal heart rhythms associated with high doses of Celexa (citalopram hydrobromide)
Welcome, my name is Steve Jackson, a pharmacist in the Division of Drug Information. On August 24, 2011, the Food and Drug Administration issued a Drug Safety Communication informing the public that the antidepressant Celexa, also marketed as the generic 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. 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.
Changes in the electrical activity of the heart, seen as prolongation of the QT interval of the electrocardiogram, or 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.
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.
At this time, FDA recommends that Healthcare Professionals be aware that:
- 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.
- Hypokalemia and hypomagnesemia should be corrected before administering citalopram. Electrolytes should be monitored as clinically indicated.
- Frequent ECG monitoring should be considered in patients with congestive heart failure, bradyarrhythmias, or patients on concomitant medications that prolong the QT interval.
- 20 mg per day is the maximum recommended dose for patients with hepatic impairment, who are greater than 60 years of age, who are CYP 2C19 poor metabolizers, or who are taking concomitant cimetidine, brand name Tagamet, because these factors lead to increased blood levels of citalopram, increasing the risk of QT interval prolongation and Torsade de Pointes.
- No dose adjustment is necessary for patients with mild or moderate renal impairment.
- Patients should be advised to contact a healthcare professional immediately if they experience signs and symptoms of an abnormal heart rate or rhythm while taking citalopram.
- Adverse events involving citalopram should be reported to the FDA MedWatch program at www.fda.gov/medwatch.
Thank you for listening. The FDA is committed to keeping healthcare professionals informed of the latest safety information. Please read the Drug Safety Communication for the complete Data Summary detailing this communication. A link to this DSC can be found at www.fda.gov/Drugs/DrugSafety . If you have drug questions, you can reach us at firstname.lastname@example.org .