Incobotulinum Toxin for the Treatment of Trigeminal Neuralgia

IncobotulinumtoxinA (Xeomin®) is a neurotoxin which inhibits the release of certain chemicals at the nerve terminals. It blocks cholinergic transmission at the neuromuscular junction by inhibiting the release of acetylcholine from motor neurons. In addition it blocks the release of Substance P (SP) and Calcitonin Gene Related Peptide (CGRP) from C fibers involved in pain perception. This study is designed to see if Xeomin® is superior to placebo in the treatment of medically refractory trigeminal neuralgia (TN). Subjects will be asked to maintain an attack diary throughout the study. They will also be asked to attend 4 office visits; Visit 1- Screening Visit, Visit 2- Injection Visit, Visit 3- Follow-Up Visit and Visit 4- Final Visit. At the end of the study the active (Xeomin®) and placebo groups will be compared to see if one group had better relief than the other.