The most effective drugs are anti-seizure medications, such as carbamazepine, gabapentin, and
phenytoin. Some antidepressants, such as amitriptyline, may help certain people.
In severe cases, when pain is difficult to treat, surgery to take pressure off the glossopharyngeal nerve may be needed. This surgery is generally considered effective. If a cause of the neuralgia is found, treatment should control the underlying problem.
You can refer http://www.nlm.nih.