Two types of therapy can be performed: oral medical therapy and local injection of drugs.
Oral pharmacological therapy to treat hemifacial spasms has proven to be scarcely effective. The most commonly used drugs are: Carbamazepine, Phenytoin, Baclofen, and Clonazepam. All these medicines, however, present side effects such as mental confusion, memory disorders, and sedation. Carbamazepine can furthermore alter the hematochemical and hepatic function. Moreover, these treatments are not very effective.
Local infiltrative treatment
The most effective treatment for hemifacial spasms is injecting botulinum toxin. In most subjects affected by hemifacial spasm, a treatment with botulinum toxin can be effective.
The botulinum toxin is injected directly into the muscle affected by the spasm or under the skin, on the surface of the muscle. The toxin paralyses the muscle partially and relaxes it thereby reducing, or at times even eliminating, the spasms.
However, the effect is temporary, from 3 to 6 months, after which the treatment needs to be repeated.
There are potential, albeit infrequent, side effects such as skin irritation on the site of the injection, a burning sensation during the injection itself, and excessive muscle weakness. Excessive hyposthenia (reduction of strength) of the periocular muscles can lead to a temporary difficulty in closing an eye or lowering an eyelid. This will require the instillation of eye drops. Other side effects include double vision or the appearance of scotomas (seeing dark spots).
If the muscle weakness affects the lower part of the face, a facial asymmetry may appear (deviation of the mouth).
All these complications are temporary and do not require any specific treatment.
While the oral medical therapy and the local administration of botulinum toxin merely control the symptoms of the pathology, surgical therapy, on the contrary, can cure the cause.
Vascular decompression performed with microsurgery is a neurosurgical methodology consisting in distancing the blood vessel from the facial nerve by placing a small foam swab between them to prevent contact.
In this manner, by eliminating the adherence between the nerve and the blood vessel, 85% of all cases lead to a total cure of the spasms. Often the improvement is gradual (a few days). Relapses are rare and can benefit from a second procedure.
The main complications of the procedure are the reduction (or loss) of hearing and a possible paresis of the facial nerve (both events are very rare with an incidence of 3-5%).
Age, other concomitant diseases, and the severity of the hemifacial spasm are other elements used to establish if a patient can be subjected to this procedure or not.