MEXILETINE
Drug Treatments for Facial Neuralgias

Disclaimer.

Mexiletine is an orally used local anesthetic, similar to lidocaine.

Mexiletine is currently used for heart rhythm disorders. It is also in experimental use for neuropathic pain, since one effect of the drug is to to damp down overactivity of peripheral nerves. Unlike externally used local anesthetics, mexiletine only appears to affect the painful nerves and thus neither numbs nor desensitizes the patient.   It is sometimes used to treat diabetic neuropathy (pain caused by nerve damage) and nerve pain in AIDS.  See the following two reports.  It is unclear if mexiletine has been tested for facial neuralgia yet.  

Efficacy and Safety of Mexiletine in the Treatment of Painful  Diabetic Neuropathy

Use of Mexiletine to treat Aids-related Peripheral Neuropathy.