No medicine is perfect. Dilantin has been so effective for some epilepsy patients that they continue to take it as part of long-term therapy.

But according to some studies, Dilantin long-term exposure could put these patients at risk for cerebral atrophy.

What Is Dilantin?

Dilantin, also known as phenytoin, is an anticonvulsant medication.

It was originally developed over a hundred years ago, then went practically unused for decades until scientists discovered it was an effective treatment for the seizures associated with epilepsy.

Even though Dilantin is as old as it is, it hasn’t been made obsolete by the introduction of newer drugs.

Today, it’s still approved by the FDA as a treatment for tonic-clonic (grand mal) and psychomotor (temporal lobe) seizures. It may also be prescribed for other, “off-label” uses at the treating physician’s discretion.

Trouble seems to arise for some patients who have been subject to Dilantin long-term exposure.

Case studies show some of these patients began to exhibit signs of cerebellar atrophy, and analysis by treating physicians points to Dilantin itself as a possible cause.

What is Cerebellar Atrophy?

Atrophy within the brain is a reduction of the volume of tissue caused by the loss of brain cells. It can be generalized atrophy, in which cells are lost throughout the brain, or focal, in which a particular part of the brain loses cells.

Cerebral atrophy can be traced to a number of different causes. It can result from disease, a head injury, or a vitamin deficiency, or it may be just result from normal aging.

Heavy alcohol use can cause cerebral atrophy, as can a stroke.

Cerebellar atrophy, sometimes referred to as cerebellar degeneration, is a type of focal cerebral atrophy that affects the cerebellum, a part of the brain that has a lot of responsibility for controlling voluntary muscle movement.

Symptoms of Cerebellar Atrophy

Patients with cerebellar atrophy typically show symptoms related to movement. They may walk with a wide-legged, unsteady walk, and movement of their limbs may be unsteady or jerky.

Speech may be slow, unsteady and hard to comprehend. The condition can also cause nystagmus, an alteration of the normal movement of the eyes.

Some patients have also reported psychiatric symptoms in addition to their physical ones.

Is Dilantin Long-Term Exposure to Blame?

Since there are many possible causes of cerebellar atrophy, scientists weren’t always quick to pin it on Diantin long-term exposure.

In one study published in 1994, researchers found that MRIs of patients with epilepsy who had been exposed to Dilantin showed “significantly more pronounced” cerebellar atrophy than did those of control subjects.

The researchers hesitated to link the cerebellar atrophy to the patient’s Dilantin long-term exposure instead of the epilepsy itself, however.

More recently, physicians have found reason to suspect a connection between Dilantin and cerebellar atrophy.

Case studies document instances of cerebellar atrophy in patients who had been subject to Dilantin long-term exposure for as long as 10 years. Causal analysis by the treating physicians in these cases points to Dilantin as the more likely culprit.