Dilantin, also known generically as phenytoin, is the grandfather of all commercially available seizure control drugs.

Discovered by a German chemist very early in the twentieth century, its chemistry was first developed to control convulsions secondary to electroshock treatment for various mental illnesses.

According to the Epilepsy Foundation, it wasn’t until 1938 that it was commercially introduced for the prevention of certain types of seizures. Unfortunately, with any medication, there are potential side effects like phenytoin induced cerebellar ataxia.

What is Phenytoin Induced Cerebellar Ataxia?

Phenytoin induced cerebellar ataxia is a loss of full autonomy over muscle movements due to an atrophy of a part of the brain known as the cerebellum. The cerebellum is located at the base of the skull behind the brain stem and is comprised of two hemispheres like many brain lobes.

This lobe has been identified as responsible for the voluntary control of muscle movements, unlike the brain stem which controls involuntary life processes such as heart beat and respiration.

In phenytoin induced cerebellar ataxia, the smooth and polished voluntary control over things like slouching or standing up straight and maintaining balance and coordination whether standing or walking may be compromised.

Other symptoms of phenytoin induced cerebellar ataxia might be surprising, however. The muscle control of the mouth and tongue with speech and even eye behavior can be affected.

Length of Treatment and Phenytoin Induced Cerebellar Ataxia

Ataxia, or the loss of complete control over muscle movements, can occur because of stroke or a disease process such as the progression of multiple sclerosis. It is usually related at least in some part to a loss of neurons or neuron connections in the cerebellum of the brain.

Here is where, according to healthline.com, close to half of the brain’s neurons reside. In terms of human progressive evolution, the cerebellum as a part of the brain is old and existed in the animal kingdom long before humans came on the scene.

The loss of neurons and neuron connections which transmit vital electrical signals is often because of lobe atrophy in this area. It may or may not be permanent, but it has been linked through a 2003 published study to treatment with Dilantin over the long haul.

Controlling for the fact that seizure disorder in general can cause such shrinkage, a previous 1994 study was able to identify smaller overall cerebellum lobes in patients taking phenytoin.

Other causes of phenytoin induced cerebellar ataxia may be a tested blood level of the drug way above the range that is considered therapeutically effective. Bringing that level down may or may not alleviate symptoms.

Changing the treatment protocol to another anticonvulsant medication altogether may help, but this should always be done under the care of the prescribing physician. Symptoms of cerebellar ataxia may be obvious or subtle but include:

• Shaking tremors
• Slow, halting movements—as if walking gingerly on broken glass
• Imbalances leading to a frequent catch in your step
• Slurred speech
• Small rapid movements of the eyes from side to side

If you or a loved one has developed cerebellar ataxia secondary to Dilantin use, you may be eligible for legal compensation.