Phenytoin toxicity has been linked with a possible increased risk of cerebellar atrophy, a deterioration of part of the brain. Phenytoin is the generic form of Dilantin, which is prescribed to treat patients suffering from epileptic seizures.

The History of Dilantin

According to Wikipedia, phenytoin or Dilantin was first discovered by a chemist from Germany known as Heinrich Blitz. This initial discovery happened in the first decade of the 20^th century and the chemist sold the patent to Parke, Davis & Co. Known as Parke-Davis, this company has a rich history of operating as one of the country’s oldest and largest drug manufacturers.

Parke-Davis didn’t immediately find a therapeutic application for phenytoin. Thirty years after its discovery, a couple of scientists outside of the organization noted that it was effective in controlling seizures and didn’t seem to have the same sedating effects of what was then used to treat epilepsy—phenobarbital. It wasn’t until 15 years later that phenytoin was approved for commercial distribution by the U.S. Food and Drug Administration (FDA).

Phenytoin had its proponents for alternative uses as well, according to this source. Jack Dreyfus had it prescribed to him for clinical depression and anxiety in 1966. Dreyfus was the founder of the Dreyfus Fund and he invested at least $70 million in an attempt to expand its approved medical applications. At this point, the drug was nearing the end of its patent cycle, so Parke-Davis allegedly didn’t match the investment with the same amount of enthusiasm.

Today, Dilantin is often referred to as the “grandfather of epilepsy medicines”.

How Does Phenytoin Work?

Phenytoin works by slowing the impulses within the brain that trigger epileptic seizures.

According to the Epilepsy Foundation, brain cells fire “at a certain rate to function normally. During a seizure, brain cells are forced to work much more rapidly than normal.”

Phenytoin keeps the brain cells from firing at this sped up level, so seizures are stopped before they can start. It is still an effective drug, but there are many alternatives on the market today with fewer side effects.

What is Cerebellar Atrophy?

The FDA says that it has received multiple adverse event reports alleging cerebellar atrophy affected patients taking phenytoin on a long-term basis and those who took a larger dose of the anti-seizure medication.

Cerebellar atrophy is the deterioration of the nerve cells in the cerebellum, the part of the brain responsible for balance and muscle coordination. The cerebellum is located under the main mass of the brain and behind the brain stem. Posture, coordination, balance, speech and precise movement are all possible with a healthy cerebellum.

Cerebellar atrophy symptoms can include:

• Uncoordinated movements of the limbs or trunk
• Difficulty walking (unsteadiness)
• Memory loss
• Slow, slurred speech
• Speech changes in tone, pitch, and volume
• Abnormal eye movements known as nystagmus

Accompanying symptoms may include:

• Headache
• Dizziness
• Changes in mental state (such as personality or behavioral changes)

Long-term Dilantin Use Can Lead to Phenytoin Toxicity

Studies show a correlation between phenytoin’s long-term use and cerebellar atrophy. Even though seizures alone can cause cerebellar atrophy, that fact was taken into account during several studies regarding phenytoin toxicity.

A 1994 study looked at the MRI results of phenytoin patients compared to those who had not received the drug. The cerebellum of the phenytoin users were significantly smaller than those of the non-treated patients.

The Annals of Neurology published another study of five epileptic patients with cerebellar degeneration. None of them had suffered recent seizures, but all of them had high levels of phenytoin toxicity. The researchers concluded the drug and not the seizures led to the cerebellar deterioration.

Another study, published in 2003, indicated that moderate to severe cerebellar atrophy occurred with long-term use of phenytoin. Children and the elderly also are vulnerable to the potent drug’s dangers.

In some cases, damage that is caught in an early stage can be treated as patients withdraw from Dilantin, easing the level of phenytoin toxicity. However, withdrawal from the medication must be overseen by a doctor.

Patients who have suffered from more severe cerebellar atrophy symptoms for a longer period of time are less apt to make a full recovery. The loss of muscle coordination is more likely to become permanent.

If you have taken Dilantin and suffered such side effects, you could be eligible for compensation through a phenytoin toxicity cerebellar atrophy lawsuit.