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Short-Lasting Unilateral Neuralgiform Headache With Conjunctival Injection and Tearing (SUNCT)


Stephen D. Silberstein

, MD, Sidney Kimmel Medical College at Thomas Jefferson University

Reviewed/Revised Apr 2023

Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attack (SUNA) are rare headache disorders characterized by extremely frequent attacks of unilateral head pain and autonomic activation.

SUNCT, like cluster headache Cluster Headache Cluster headaches cause excruciating, unilateral periorbital or temporal pain, with ipsilateral autonomic symptoms (ptosis, lacrimation, rhinorrhea, nasal congestion). Diagnosis is clinical... read more , is a primary headache disorder characterized by unilateral pain in the trigeminal nerve distribution and by autonomic manifestations. As such, SUNCT and cluster headaches are sometimes grouped together as trigeminal autonomic cephalgias.

Short-lasting unilateral neuralgiform headache attacks with cranial autonomic symptoms (SUNA) is similar to SUNCT, but the autonomic manifestations include conjunctival injection or tearing, but not both. Other manifestations of SUNCT and SUNA are similar. SUNCT and SUNA are considered short-lasting unilateral neuralgiform headaches.

In SUNCT, pain paroxysms are typically periorbital, are extremely frequent (up to 200/day), and last from 5 to 250 seconds. Conjunctival injection is often the most prominent autonomic feature; tearing may also be obvious.

Diagnosis of SUNCT

  • Clinical evaluation

Diagnosis of SUNCT is clinical. MRI or CT is done to rule out other possible causes such as a pituitary tumor

  • It has no refractory period.

  • Pain occurs predominantly in the ophthalmic division of the trigeminal nerve.

  • Attacks are not triggered by cutaneous stimuli.

  • Indomethacin does not relieve symptoms, as it does in some other headache disorders.

Treatment of SUNCT

  • For terminating a cycle of acute attacks, IV lidocaine

  • For prevention, antiseizure medications and/or occipital nerve stimulation or blockade

Treatment of SUNCT can include IV lidocaine to terminate a cycle of acute attacks and, for prevention, antiseizure medications (eg, lamotrigine, topiramate, gabapentin) and occipital nerve blockade (eg, with a mixture of lidocaine and methylprednisolone) or stimulation.

In one clinical trial, IV lidocaine can terminate the cycle of acute attacks in most patients when it is given for 7 to 10 days (1 Reference Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) and short-lasting unilateral neuralgiform headache attack (SUNA) are rare headache disorders characterized... read more ). It is the most successful treatment, followed by lamotrigine, followed by oxcarbazepine.


  • 1. Lambru G, Stubberud A, Rantell K, et al: Medical treatment of SUNCT and SUNA: A prospective open-label study including single-arm meta-analysis. J Neurol Neurosurg Psychiatry 92 (3):233–241, 2021 doi: 10.1136/jnnp-2020-323999 Epub 2020 Dec 24.

Drugs Mentioned In This Article

Drug Name Select Trade
Indocin, Indocin SR, TIVORBEX
7T Lido, Akten , ALOCANE, ANASTIA, AneCream, Anestacon, Aspercreme with Lidocaine, Astero , BenGay, Blue Tube, Blue-Emu, CidalEaze, DermacinRx Lidogel, DermacinRx Lidorex, DERMALID, Ela-Max, GEN7T, Glydo, Gold Bond, LidaMantle, Lidocan, Lidocare, Lidoderm, LidoDose, LidoDose Pediatric, Lidofore, LidoHeal-90, LIDO-K , Lidomar , Lidomark, LidoReal-30, LidoRx, Lidosense 4 , Lidosense 5, Lidosol, Lidosol-50, LIDO-SORB, Lidotral, Lidovix L, LIDOZION, Lidozo, LMX 4, LMX 4 with Tegaderm, LMX 5, LTA, Lydexa, Moxicaine, Numbonex, ReadySharp Lidocaine, RectaSmoothe, RectiCare, Salonpas Lidocaine, Senatec, Solarcaine, SUN BURNT PLUS, Tranzarel, Xyliderm, Xylocaine, Xylocaine Dental, Xylocaine in Dextrose, Xylocaine MPF, Xylocaine Topical, Xylocaine Topical Jelly, Xylocaine Topical Solution, Xylocaine Viscous, Zilactin-L, Zingo, Zionodi, ZTlido
Lamictal, Lamictal CD, Lamictal ODT, Lamictal XR, Subvenite
EPRONTIA, Qudexy XR, Topamax, Topamax Sprinkle, Topiragen , Trokendi XR
Active-PAC with Gabapentin, Gabarone , Gralise, Horizant, Neurontin
A-Methapred, Depmedalone-40, Depmedalone-80 , Depo-Medrol, Medrol, Medrol Dosepak, Solu-Medrol
Oxtellar XR, Trileptal
NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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