FDA Adds Heart Warning to Quetiapine's Label

The FDA has added a warning to the label of the atypical antipsychotic quetiapine (Seroquel) cautioning about potential increases in the QT interval.

Postmarketing cases of QT prolongation have been reported in some 17 patients, according to the New York Times. These patients had overdosed on quetiapine, had other illnesses, or were taking other medications that can cause electrolyte imbalance or QT prolongation.

The new label warns against using quetiapine in conjunction with such drugs, including:

• class 1A antiarrhythmics (e.g., quinidine, procainamide)

• class III antiarrhythmics (e.g., amiodarone, sotalol)

• antipsychotics (e.g., ziprasidone, chlorpromazine, thioridazine)

• antibiotics (e.g., gatifloxacin, moxifloxacin)

• other drugs associated with QT prolongation (e.g., pentamidine, methadone)

Clinicians should also avoid prescribing the drug in patients who have a history of arrhythmias, hypokalemia, hypomagnesemia, or congenital QT prolongation.