Table 1. Diagnostic criteria for TN set forth by major specialty societies.

Specialty societies have defined diagnostic criteria for TN [3,7,12-14]

MS: multiple sclerosis; TN: trigeminal neuralgia

Characteristic	Third edition of International Classification of Headache Disorders	International Association for the Study of Pain	European Academy of Neurology
Triggers	Innocuous stimuli along the trigeminal distribution	Innocuous stimuli along the trigeminal distribution, but pain may arise spontaneously	Not mentioned
Pain	Paroxysms with or without concomitant underlying pain	Paroxysmal pain but concomitant underlying pain is possible	May be purely paroxysmal or paroxysmal plus concomitant persistent pain
Painful paroxysms	Lasts from less than one second to two minutes. Severe intensity. Often has an “electric” or stabbing quality	Few seconds to a maximum of two minutes. Severe intensity	Painful paroxysms
Location	Along distributions of trigeminal nerve, typically unilateral	Along distributions of the trigeminal nerve, typically unilateral. TN secondary to MS is sometimes bilateral	Along distributions of trigeminal nerve, usually unilateral, but younger and secondary patients may have bilateral symptoms
Trigeminal sensory deficits	Not mentioned	Not mentioned	More common in those with secondary TN than primary