View source for Trigeminal neuralgia

==Background==
[[File:Gray778.png|thumb|Trigeminal nerve anatomy.]]
[[File:Gray784.png|thumb|Dermatome distribution of the trigeminal nerve: V1 (green), V2 (red), and V3 (yellow).]]
*Also known as tic doulourex

==Clinical Features==
*Paroxysms of severe unilateral pain in trigeminal nerve distribution lasting only seconds <ref>Cruccu G, et al. Trigeminal neuralgia. N Engl J Med. 2020;383(8):754-762. PMID 32813951</ref>
*Normal neuro exam 
*No pain between paroxysms
*Variant with headache
*More common in Middle aged women
*Frequently triggered by minimal stimuli (e.g. light touch, gentle breeze)

==Differential Diagnosis==
{{Headache DDX}}
{{Facial paralysis}}

==Evaluation==
*Sensory loss, bilateral involvement, and younger age (<40) are associated with a higher risk of secondary TN, but their absence does not rule out secondary TN
*Consider [[head CT|CT]]/[[brain MRI|MRI]] in these patients to rule out structural etiology
*<5% of patients have V1 distribution, examine carefully for [[zoster]] in these patients

==Management==

===[[Carbamazepine]]===
*First-line agent with 75% success rate initially 
*Proposed Mechanism: Decreases the response of neurons to peripheral stimulation 
*Started at 100mg one to two times per day 
*Increase by 100-200mg every 3 days 
*Usual maintenance dose is 400-800mg (rare >1500mg) 
*Metabolized by liver (cytochrome P450) 
**LFTs monitored on outpatient basis 
*Pain relief occurs within several hours to days (94% within 48 hours) 
*Target serum concentration is 24-43 μmol/L 
**If unsuccessful, [[phenytoin]] 200-400mg/day is used in combination

===Other agents===
*[[Baclofen]], [[clonazepam]], [[valproic acid]], [[lamotrigine]], [[gabapentin]], [[oxcarbazepine]], [[topiramate]]

===Surgery===
*Posterior fossa microvascular decompressive surgery 
**Approximately 50% of patients will require surgery
*Successful in 70% of patients

==Disposition==
*Typically outpatient

==See Also==
*[[Headache]]

==References==
*J Pain Symptom Manage 2001; 21(6):506-510. 

[[Category:Neurology]]