December 20, 2011 — The FDA is revising the safety labeling on Multaq (dronedarone), a popular anti-arrhythmiac heart medication, after recent studies found that users have almost twice the risk of serious cardiovascular events, including stroke, myocardial infarction, systemic embolism, and death from cardiovascular causes.
The new label changes include the following safety warnings:
- Multaq should not be prescribed to people with permanent atrial fibrillation
- People who are taking Multaq must have their cardiac rhythm monitored every three months via electrocardiocram (ECG). If the person has permanent atrial fibrillation, Multaq should be stopped.
- Multaq only reduces hospitalization rates in people with non-permanent atrial fibrillation
- Patients given Multaq should also be given medication to reduce the risk of blood clots
The FDA has approved Multaq for the treatment of atrial flutter, and paroxysmal or persistent atrial fibrillation. It is not approved for the treatment of permanent atrial fibrillation. The drug-maker, Sanofi-Aventis, had attempted a study of the medication on patients with permanent atrial fibrillation, but stopped the study prematurely after finding a dramatic increase in the number of life-threatening cardiovascular events.
Multaq has been approved for the treatment of atrial fibrillation since a study in 2009, which based its safety conclusions on the reduced rate of hospitalization. The FDA still believes that Multaq is beneficial for patients with this type of abnormal heart rhythm.
This new safety warning follows another FDA safety update in January of 2011, which was prompted after two reported cases of acute liver failure that required liver transplantation. While a patient is taking Multaq, it is recommended that they receive liver enzyme tests, especially during the first six months.
Atrial fibrillation is the most common type of heart arrhythmia, which is an abnormal heart rate or “fluttering.” The heart beat may be irregular, and is often rapid. It can cause poor blood flow to the rest of the body. While the heart is fibrillating, the upper chambers of the heart beat out of coordination with the lower chambers. The most serious risk is that blood will pool in the upper chambers, forming blood clots, that the heart will pump to the brain, causing a stroke. Atrial fibrillation can also weaken the heart and cause heart failure.