A new study of trigeminal neuralgia

Trigeminal neuralgia is a very painful and debilitating condition (Here is a review article I wrote for physicians). Fortunately, it is relatively infrequent – affecting 0.3% of the population, compared to 12% afflicted by migraines. This explains relative paucity of studies of this condition. A group of neurologists at the Danish Headache Center studied 158 consecutive patients with trigeminal neuralgia (TN) seen at their center over a period of one year. They published their findings in the journal Headache.

Average age of onset of pain was 53 years. TN was more common in women than men (60% vs 40%) and more common on the right side (56%). When only one of the three branches of the trigeminal nerve were affected, the first and the second were involved in 69% of cases and the third branch (lower third of the face) alone was involved in only 7% of sufferers.

The pain of trigeminal neuralgia is described the same way by almost all sufferers – it feels like a strong electric shock. It can be triggered by chewing, brushing teeth, speaking, air movement from wind or air conditioner, and at times it occurs without any provoking factor. In this study, half of the patients reported having a more persistent but milder pain in addition to the typical stabbing, electric-like pain. One fifth of patients reported to have some tearing on the side of pain and in 17% there was some loss of sensation over the area of pain.

Treatment of TN usually begins with epilepsy drugs,such as carbamazepine (Tegretol) or oxcarbazepine (Trileptal). Although 89% of patient in this study reported some improvement, only 56% of them were taking these medications because in others they caused unacceptable side effects. Other drugs that can be helpful for TN include baclofen (a muscle relaxant) and Botox injections. I’ve treated a handful of patients with TN with Botox
and about half of them responded. Botox is injected into the area of pain, which tends to be small and only a very small amount of Botox needs to be injected. Injections of Botox are safer than any oral medication, but depending on the area injected, they can cause cosmetic side effects – asymmetric appearance of the face. Botox is approved by the FDA for chronic migraines but not TN, which means that insurance companies are not likely to pay for it. However, only about one tenth of the amount of Botox used for migraine is needed to treat TN, the cost is much lower.

The authors plan to provide additional information about this group of patients in future publications.