TABLE 1

Key symptoms of trigeminal neuralgia and differential diagnosis

Key symptoms	Other possible symptoms	Differential diagnosis
Paroxysmal pain Sharp and shooting Lasts seconds to minutes Provoked by light touch	Burning, prickling, dull tender constant background pain	Trigeminal neuralgia with concomitant, continuous pain
Trigeminal nerve innervation area	Interparoxysmal pain	Temporomandibular disorder
Pain cannot be evoked between attacks (refractory period)	Autonomic symptoms^a	SUNCT and SUNA
Periods of remission or relapse	Sensory change^b	Painful trigeminal neuropathy
Abrupt onset	After eating	Dental, cracked tooth

↵a Some facial reddening and tearing, sometimes on both sides, may be seen during acute pain paroxysms. If more pronounced with strictly unilateral conjunctival reddening, eyelid droop, nasal blockage, then consider SUNCT and SUNA.
↵b During a relapse of trigeminal neuralgia and especially just after paroxysms of pain, there may be subtle transient unilateral sensory change in the area innervated by the trigeminal nerve. The presence of permanent sensory alterations and atypical features such as absent refractory period and no pain remission raise the possibility of trigeminal nerve damage and painful trigeminal neuropathy.
SUNA = short-lasting unilateral neuralgiform headache attacks with autonomic features; SUNCT = short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing