Trigeminal Neuralgia is a pain the occurs in the distribution of the trigeminal nerve that supplies enervation to the face.  The pain usually occurs only on one side of the face.  The pain is described as shock-like sensations that occur in spurts lasting just a few seconds to a minute.  There are trigger areas on the face that provoke these attacks.  Even the slightest touch can trigger the pain.  It can also be triggered by brushing teeth, shaving or washing.  In between attacks of trigeminal neuralgia, the patient is usually pain free.  MRI of the brain is indicated to look for intracranial causes of the disease as well as multiple sclerosis.  Abnormal blood vessels that compress the trigeminal nerve are often the cause of the problem.  Although other causes of facial pain can be confused with trigeminal neuralgia, the diagnosis is usually straightforward.  Treatment of trigeminal neuralgia is usually accomplished with carbamazepine.  The response to this medication is usually dramatic.  Baseline blood work should be taken prior to initiating therapy.  This medication can cause serious hematologic problems and must be supervised carefully by a physician.  If carbamazepine does not work, other medications such as gabapentin and baclofen have also been used.  If the pain is unresponsive to medications or if the side effects of the medications are not tolerated, other invasive modalities of treatment may be used.  Destruction of the gasserian ganglion, by injection of glycerol, radiofrequency lesioning, or surgical decompression have all been tried with varying degrees of success.