Ventricular tachycardia after initiation of fingolimod.

Fingolimod, a sphingosine-1-phosphate receptor modulator, is used for the treatment of relapsing-remitting multiple sclerosis. It is well known to cause bradyarrhythmias. We present a 63-year-old woman who was admitted to the hospital with sustained monomorphic ventricular tachycardia 2 weeks after fingolimod initiation. Further evaluation showed that the patient's ventricular tachycardia was most likely secondary to her medication. Medical practitioners need to be aware of such possible life-threatening side effects while using fingolimod.