[Treatment of trigeminal neuralgia with vincristine iontophoresis. A clinical pilot study.].

Treatment of chronic pain disease is a scientific and clinical challenge encountered in all branches of medicine. Essential trigeminal neuralgia and chronic pain situations are noted for their exceptionally marked severity and also for their psychic and social consequences. It is not rare for a primarily somatic pain syndrome to develop into a painful disease in its own right, which is highly refractory to treatment. In transcutaneous iontophoresis of vincristine the neurotoxic effect of the alkaloid is employed locally and in a controlled manner. Iontophoresis of a microtubule inhibitor (vincristine, vinblastin) to the skin induces transganglionic degenerative atrophy of the central terminals of primary sensory neurons. Vincristine iontophoresis was applied in 33 patients hitherto unsuccessfully treated with various other methods. In 78% of the cases, attenuation of the pain was achieved. This noninvasive therapy proved to be free of side effects.