Trigeminal neuralgia is a pain syndrome characterised by severe unilateral pain (10% of cases are bilateral)

The vast majority of cases are idiopathic but compression of the trigeminal roots by tumours or vascular problems may occur.

Triggers:

• the pain is commonly evoked by light tough - including washing, shaving, smoking, talking, brushing teeth
• cold weather
• spicy food, caffeine, citrus fruits

PC

• unilateral brief shock like pains, abrupst in onset and termination, limited to one or more divisions of the trigeminal nerve
• small areas in the nasolabial fold may be particularly susceptible
• pains usually remit for variable periods

Red flag symptoms suggesting an underlying cause:

• Sensory changes
• Deafness or other ear problems
• History of skin or oral lesions that could spread perineurally
• Pain only in the ophthalmic division of the trigeminal nerve (eye socket, forehead, and nose), or bilaterally
• Optic neuritis
• A family history of multiple sclerosis