Trigeminal neuralgia is a condition that affects the trigeminal nerve, the nerve which provides the sensory innervation of the skin on the face. The condition causes a sudden, severe, stabbing facial pain near the nose, lips, cheek, eye or ear. The incidence of trigeminal neuralgia is three to five new cases per 100,000 people each year. Non-antiepileptic drugs, such as baclofen and tocainide, have been used to treat trigeminal neuralgia since the 1970s.
Three randomized controlled trials, each with an unclear risk of bias, compared the three different non-antiepileptic drugs tizanidine, tocainide and pimozide with carbamazepine, which is the standard drug treatment. Tizanidine and tocainide did not produce significantly more benefit than with carbamazepine. Tocainide had severe side effects. Pimozode produced significantly more improvement than carbamazepine but side effects were very common. In a fourth trial with a low risk of bias proparacaine hydrochloride eye drops did not show any significant benefit.
Further well designed randomized controlled trials are needed to establish whether non-antiepileptic drugs are beneficial in trigeminal neuralgia.