Date amended:
Statements of Principles
Current RMA Instruments
Reasonable Hypothesis
77 of 2015
Balance of Probabilities
78 of 2015
Changes from previous instruments


ICD Coding
  • ICD-9-CM Codes: 350.1
  • ICD-10-AM Codes: G50.0
Brief description:

There are two SOPs concerning the trigeminal (5th cranial) nerve, being trigeminal neuralgia and trigeminal neuropathy. The trigeminal nerve provides sensation to the face, the top of the head, gums and anterior tongue, and motor function to the muscles of mastication (chewing).

Trigeminal neuralgia is a paroxysmal facial pain disorder in the trigeminal nerve sensory distribution which is precipitated by various innocuous stimuli and the paroxysms are of short duration and are separated in time by asymptomatic intervals.

Trigeminal neuropathy is a disease or injury of the trigeminal nerve or ganglion which involves loss of function of the trigeminal nerve, with objective signs as well as symptoms.

There are other facial pain syndromes that are not covered by either SOP.

Confirming the diagnosis:

To confirm the diagnosis a report from a specialist neurologist is required.

Additional diagnoses covered by these SOPs
  • Classical trigeminal neuralgia
  • Symptomatic (secondary) trigeminal neuralgia
  • Tic Douloureux
Conditions not covered by these SOPs   
  • Atypical facial pain#
  • Cluster headache*
  • Dental pain#
  • Glossopharyngeal neuralgia#
  • Herpetic neuralgia# - That is pain at the time of the infection   (Herpes Zoster)
  • Migraine* 
  • Periodontal pain*   (Periodontitis)
  • Peripheral neuropathy*
  • Peripheral painful post-traumatic trigeminal neuropathy*    (Trigeminal neuropathy)          
  • Persistent idiopathic facial pain#         
  • Postherpetic neuralgia#
  • Short-lasting unilateral neuralgiform headache attacks with conjunctival injection and tearing (SUNCT) #
  • Trigeminal neuropathy*                        
  • Trigeminal orofacial neuropathic pain syndromes#

* another SOP applies  - the SOP has the same name unless otherwise specified

# non-SOP condition

Clinical onset

The clinical onset is the earliest time prior to the confirmation of the disease, that the pathognomonic set of symptoms could be documented.

Clinical worsening

A clinical worsening in an episodic disorder such as trigeminal neuralgia is not simply triggering an episode of pain, but would require that the whole episodic pain pattern is worse in intensity, and or increased in frequency and for aggravation (as opposed to aggravation of signs and symptoms) that this clinical worsening is permanent.

If it is thought that there is a clinical worsening, it is recommended that an expert opinion be sought from a neurologist to evaluate whether the clinical worsening was out of keeping with the natural history of the underlying pathology.

Bajwa et al (2014)[i] states “the course of TN [trigeminal neuralgia] is variable” and “Episodes may last weeks or months, followed by pain-free intervals”, “Recurrence is common..” and “Most often, the condition tends to wax and wane in severity and frequency of pain exacerbations” and “however, there are no pure natural history studies of TN, most likely because the severity of the pain leads to intervention.”



[i] Bajwa, Z., Ho, C. and Khan, S. 2014, ‘Trigeminal neuralgia’, UpToDate, September 3rd,…