Trigeminal Nuclei, Trigeminal Neuralgia, and Epileptic Mechanisms

Abstract

ABSTRACT.The paroxysms of excruciating pain in trigeminal neuralgia are most likely due to epileptiform discharges in the trigeminal system. Drugs that prevent these attacks, such as carbamazepine and phenytoin, depress excitatory transmission and facilitate segmental or afferent inhibition in the trigeminal nucleus. Baclofen resembles carbamazepine and phenytoin in its ability to depress segmental excitation and facilitate segmental inhibition in the trigeminal nucleus. Clinical trials have shown that baclofen is also an effective drug for the treatment of trigeminal neuralgia. In contrast to carbamazepine and phenytoin, baclofen does not depress the excitatory or inhibitory mechanisms descending from the reticular formation, and clinical trials showed that baclofen is not an antiepileptic drug. These observations imply that the facilitation of segmental inhibition is an important characteristic of drugs effective against trigeminal neuralgia, and that the ability to prevent the propagation of paroxysmal...