Facial Nerve Pain

Is there a remedy to treat facial nerve pain? My husband (50 y.o.) has had four sinus surgeries ("non-invasive") for chronic sinusitus to remove mucus and polyps from the top specialist at Massachusetts Eye and Ear. (He has been thoroughly tested and is not allergic to anything, e.g., dust, pollen, animals, etc.).
The recurrent sinusitus has cleared (Goldenseal and Echinacea tea, vitamin C, and other herbal supplements!) but he is in absolutely terrible pain. It prevents him from working, completing a thought, and enjoying life (anything) at all. The pain is primarily behind his right eye (Ethmoid Sinus), which is very close to the brain and probably explains his change in thought patterns. At this point, it has been realized by the doctor that it is nerve pain now (from the surgeries) rather than sinusitus because every time we went back the doctor he did not see any blockages (recurrent sinusitus). He referred us to a neurologist at Beth Isreal Hospital Pain Clinic in Boston who gave him Neurontin. It helped the pain a bit but changed his personality (moods) more. I have him scheduled next week at the Mass. General Hospital Pain Clinic. It is one of the few facilities that treat facial pain; most pain clinics only treat from the neck down. We were told MGH performs accupuncture, steroid injections in the face, etc.
At this time I give him facial massages with peppermint tincture oil, ice, calming teas (kava kava, valerian) but to no long term alleviation.
I have exhausted researching homeopathic remedies to help relieve his chronic pain.
Any advice of homeopathic remedies we can try would be truly appreciated.

I don't practise homeopathic medicine, but can recommend some herbs.
Chamomile, Valerian and White Willow bark are commonly used in nerve pain. A more potent herb is Jamaica Dogwood. With its nerve relaxing and antispasmodic actions, it is used specifically in nerve pain. Gelsemium sempervirens (Yellow Jasmine) is a more powerful nerve relaxant, but because the therapeutic dose is close to a dangerous dose, the herb can be used only by practitioners. It is available as a homeopathic preparation that is safe for home use.
Herbs that nourish nerve tissue include: St. John's wort, taken as a tea, a tincture or used externally as a oil or poultice; Oats, taken as porridge or oatstraw tea; and Skullcap, taken as a tea or tincture. Vitamin B complex also helps to nourish nerve tissue.