Multiple sclerosis (MS) is a debilitating disease that causes the immune system to attack the protective covering of nerves in the body. A commonly-used epilepsy drug may help prevent nerve damage in patients suffering from this auto-immune disease.
Phenytoin, a commonly-used and cheap drug for seizure, shows promise in preventing damage caused by an auto-immune response brought by MS. In a new study, researchers from the University College London, Institute of Neurology, found that phenytoin protected neural tissue in patients with optic neuritis, can potentially prevent blindness in people with MS.
"About half of people with MS experience at some point in their life a condition called acute optic neuritis, in which the nerve carrying vision from the eye to the brain gets inflamed," Dr. Raj Kapoor from the National Hospital for Neurology and Neurosurgery said.
MS may lead to sudden partial or total blindness. The condition is usually characterized by a "foggy or blackened" vision. Though the eyesight may recover or come back, each MS attack on the eye damages the nerves.
The study, which was presented at the American Academy of Neurology's 67th Annual Meeting in Washington, D.C., analyzed data from 86 individuals who are suffering from acute optic neuritis. The researchers divided the individuals into treatment and control groups. The treatment group received the anti-seizure drug while the control group received a placebo in the course of three months.
With the use of medical imaging, the researchers examined and measured retinal thickness at the start of the study and after six months. They found that on average, the treatment group incurred 30 percent reduced damage to the nerve layer than those who received placebo treatment.
The researchers also found that the macular volume, the part of the retina which is most sensitive to light, increased by 34 percent in those who took phenytoin. The drug works as an effective protective component for nerves because it prevents the fatal build-up of sodium in nerve cells.
The team wanted to focus on the sodium channel and its effects on neuroprotection. In areas where there is inflammation, the axons of nerve cells are bombarded with sodium, which causes the influx of calcium. When this happens, cell death occurs. If sodium entry into cells can be reduced and eventually blocked, it shows promise in preventing cell death.
"Eyesight is key to many important aspects of life, such as working, driving and participating in social activities," said Dr. Kapoor. He added that if the study is confirmed by larger researches and investigations, the treatment may improve treatment of optic neuritis and eventually, prevent nerve damage, blindness and other MS complications.
Roughly 400,000 people in the United States suffer from MS with 10,000 new cases diagnosed every year. The disease is more common in women than in men and commonly seen in people living in Europe, the United States, Canada, New Zealand, and sections of Australia.
The study was published in the journal Lancet Neurology.
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