Trigeminal neuralgia in a patient with multiple sclerosis: Coincidental? An attack? Teriflunomide-induced?

Trigeminal neuralgia attributed to multiple sclerosis (TNMS) occurs in 2% to 5% of patients with multiple sclerosis (MS). Although treatment strategies are similar to those for classic trigeminal neuralgia, TNMS tends to become medically resistant and require polytherapy. Demyelinating lesions in critical regions are the most common etiology. However, therapies used to treat MS may trigger trigeminal neuralgia, as well as other pain disorders, like migraines or daily headaches. Presently reported is the case of a patient with MS who suffered severe trigeminal neuralgia 5 months after switching to teriflunomide, an oral immunomodulator drug approved for relapsing-remitting MS, and a discussion of possible etiological factors for the development of trigeminal neuralgia.