Celexa doses greater than 40 mg are no longer recommended by the FDA because they may be associated with increased risk of abnormal heart electrical activity.
While it is surprising, a widely used antidepressant called Celexa (Citalopram) was the subject of a Safety Communication from the FDA today. (Visit www.fda.gov to see their Safety Communication). The important thing about this alert is that abnormal changes in the electrical activity of the heart appear to be dose-related. The crucial dose appears to be 40 mg. More than this can prolong the QT interval and can lead to abnormal heart rhythms.
What the FDA has done is to notify healthcare professionals and patients that doses greater than 40 mg should no longer be used. This DOES NOT mean that Celexa is a bad antidepressant. There have been many medicines found to have undesirable effects that happen with higher doses, while providing strong therapeutic benefits in lower doses.
Let’s take a closer look. Your heart actually uses a system of electrical impulses to contract and work as a pump. It’s essential that these contractions (driven by electrical activity) happen in an organized and regular way. Specific measurements in an electrocardiogram tell your doctor if the usual series of contractions and relaxation are happening normally. Changes signify effects that may be dangerous. One widely reported and written about effect of some medicines is a change in the QT interval.
While QT changes are beyond the scope of this site, the important thing is that QT lengthening (prolongation) can lead to a very dangerous abnormal heart rhythm called Torsade de Pointes. Torsade de Pointes can be fatal. Risk of QT interval prolongation can be more likely in people who:
1) Have underlying heart problems (such as congestive heart failure and slow heart rhythms called bradyarrhythmias)
2) Are predisposed to low blood magnesium levels
3) Are predisposed to low blood potassium levels.
Some of you may remember a recent caution from the FDA (reflected in the Essential Guide to Prescription Drugs, Update on Proton Pump Inhibitors, focus on Nexium) saying that prolonged use (generally more than a year) of Nexium may lead to lower magnesium. It appears from this new data on Celexa that prolonged use of Nexium in people taking this drug should be reviewed with caution by your doctor.
The FDA recommends that doses larger than 40 mg no longer be used. It also continued to note that Celexa (citalopram) should NOT be used in people with congenital long QT syndrome and that people with slow abnormal heart rhythms, congestive heart failure and predisposition to low potassium or magnesium are at higher risk of Torsade de Pointes. The FDA had additional recommendations for healthcare professionals and Patients in the safety communication.
As usual, the FDA encouraged reporting of adverse events or side effects from medicines atwww.fda.gov/MedWatch/report.htm by patients and healthcare professionals. Calls can also be made to 1-800-332-1088 to ask for a reporting form. The form can then be filled out and mailed or faxed to 1-800-332-0178.
Talk to your doctor about any concerns you have regarding your medicines, and Celexa (citalopram) in particular.