Patients with epilepsy who take certain anti-seizure medications are at risk of suffering from Dilantin cerebellar atrophy.

Dilantin, known generically as phenytoin, is one of the oldest drugs on the market prescribed to treat tonic-clonic (grand mal) and psychomotor (temporal lobe) seizures. It’s also used to treat seizures that occur during or after brain surgery.

According to the Epilepsy Foundation, a seizure occurs when a brain cells either send too many messages or stop sending messages. The chemical changes that occur in nerve cells when they fire too much or too little electrical activity can result in seizures.

When a person is having a seizure, their brain cells are firing more rapidly than normal. Dilantin works by stopping the brain cells from firing at the speed needed to induce a seizure. Seizures are basically stopped right when they are about to begin.

The Epilepsy Foundation says, “Epilepsy is the fourth most common neurological disorder and affects people of all ages.”

The diagnosis of epilepsy follows two unprovoked seizures that weren’t caused by another known medical condition, such as withdrawal from drugs or alcohol or extremely low blood sugar. Once epilepsy is diagnosed, Dilantin can help control many types of seizures, but is a very potent medicine that must be taken as prescribed.

Cerebellar Atrophy: Overview

The cerebellum is a small structure in the brain which is in charge of coordination and balance. When this structure is damaged by injury or disease, it can lead to serious side effects. When the nerve connections in the cerebellum are continuously damaged, leading to nerve death, it is called cerebellar atrophy or cerebellar degeneration.

Patients with cerebellar atrophy may exhibit a variety of issues, including:

• Inability to complete smooth, precise movements
• Tremors of the hands
• Uneven, lurching gait
• Rapid, uncontrolled eye movements
• Lack of balance
• Jerking of the arms or legs
• Difficulty sitting still because of bobbing movements of the trunk
• Change in pitch, tone or volume of speech
• Headaches
• Personality changes

A patient with cerebellar atrophy often will have trouble completing daily tasks that require fine motor skills. Brushing the teeth or buttoning one’s clothing become difficult when the hands are experiencing tremors.

A number of conditions can lead to cerebellar atrophy. Strokes can cause the condition if blood flow or oxygen to this part of the brain is impeded.

Cerebellar degeneration may also appear in other cerebellar or degenerative nervous system disorders including cerebellar cortical atrophy, multisystem atrophy, olivopontocerebellar degeneration, and progressive degenerative disorders. Multiple sclerosis, a condition during which the immune system attacks the insulation around nerve cells, is also a notable cause of cerebellar atrophy in cases where the disease affects the cerebellum.

Acquired conditions may also lead to cerebellar degeneration. Chronic use of alcohol can cause temporary or permanent damage to the cerebellum, which can cause symptoms of cerebellar degeneration. The condition may also be acquired as a result of paraneoplastic syndromes which occur when the body is attempting to fight cancer.

Although these are the more notable causes of cerebellar degeneration, the disease has also been recorded in patients taking Dilantin.

Understanding Dilantin Cerebellar Atrophy

Patients who take Dilantin for a long time are at an increased risk of suffering from Dilantin cerebellar atrophy. The cerebellum is the part of the brain that controls movement, coordination and speech. Research has shown this portion of the brain is particularly vulnerable to long-term Dilantin use and to Dilantin toxicity.

Doctors understand that years of uncontrolled seizures can cause cerebellar atrophy, too, but that has been taken into account in several studies. The MRI films of patients who had been taking Dilantin for years compared with those who had not were compared back in 1994. That study determined the cerebelli of the non-users were healthy and larger compared with that part of the brain in the patients who had been taking Dilantin for a long time.

“Cerebellar atrophy may be seen in phenytoin-exposed patients with epilepsy in the absence of generalized tonic-clonic seizures or preexistent brain damage,” the researchers concluded. “Whether it is the phenytoin or the seizures that play the primary etiologic role remains unanswered. These factors may be synergistic.”

Other studies indicate Dilantin toxicity, which is a buildup of too much of the drug in the bloodstream, can lead to an increased risk of cerebellar atrophy.

In some cases, the brain has deteriorated beyond the point of being able to recover from the damage. In other instances, patients might see improvement of some symptoms of brain atrophy if a doctor closely monitors the withdrawal of Dilantin and the drug is stopped.