Epileptic disease is characterised by enhanced brain excitability. Low frequency repetitive transcranial magnetic stimulation (rTMS) can be an effective treatment for refractory frontal epilepsy. Thought, physiological mechanisms of its effectivity are still unknown. It is yet possible to evaluate cortical excitability and inhibition with TMS-coupled electromyography before and after rTMS sessions ; this could provide clues for basic mechanisms of rTMS effects on the epileptic brain. We assume that rTMS decrease brain excitability by improving brain inhibition. Such an information could help for treating patients with both pharmacological and non-pharmacological methods.