In neurology, paroxysmal syndromes are well-known, eg, as manifestations of multiple sclerosis. We report a patient with meningeal carcinomatosis, who presented with therapy-refractory nausea and vomiting. The clinical suspicion of a paroxysmal syndrome prompted a trial of carbamazepine, which resulted in complete cessation of the symptoms. In cancer patients with central nervous system (CNS) involvement and therapy-refractory symptoms with sudden onset, carbamazepine treatment should be considered.