Dilantin induced cerebellar atrophy has been a concern in the United States for years, due to the effects of phenytoin toxicity linked to the epilepsy medication. Indeed, several studies have found that higher exposure levels of phenytoin increase the likelihood of cerebellar atrophy, with scientists suspecting a correlation as far back as 1994.

The first study indicating that phenytoin patients could be at risk for Dilantin induced cerebellar atrophy was published in August 1994 in the Archives of Neurology. The study analyzed MRI diagnostic images of phenytoin patients and found that they had significantly smaller cerebella compared to non exposed patients.

Cerebellar atrophy is a form of focal cerebral atrophy in which the cerebellum deteriorates and loses vital neurological connections. The cerebellum sits under the brain stem and is responsible for voluntary functions like walking and talking, which ultimately affects the patient’s balance and ability to communicate.

There are a number of factors that can contribute to this condition, with Dilantin induced cerebellar atrophy documented as a potential cause in several different studies. including:

• a study published in December 2000 in the Journal of Postgraduate Medicine, which was a case study of a young boy who had developed cerebellar atrophy allegedly from high levels of phenytoin exposure.
• a study published in July 2003 in the medical journal Seizure, which consisted of 56 epilepsy patients who were prescribed phenytoin for over two months. The study also indicated that high levels of phenytoin exposure increase the likelihood of Dilantin induced cerebellar atrophy.
• a study published in November 2013 in the Indian Journal of Pharmacology, which was a case study of a 16 year old boy who had allegedly developed Dilantin induced cerebellar atrophy, who was prescribed the medication after suffering a history of seizures.

As of January 2016, there have been approximately 11,836 Dilantin injury reports submitted to the FDA, with nine of the cases allegedly involving Dilantin induced cerebellar atrophy.

Overview of Dilantin and Cerebellar Atrophy

Dilantin was approved by the FDA in 1982, and is one of the oldest and most reliable antiepileptic medications in the United States. This medication works by slowing down the electrical signals in the brain, which prevents the onset of seizures.

While this drug has helped numerous patients, the risk of Dilantin induced cerebellar atrophy has become a prevalent concern. Dilantin patients who develop cerebellar atrophy will develop symptoms including:

• an unsteady, lurching, or jerky walk
• slow, unsteady, jerky movements in arms or legs
• slowed and slurred speech
• nystagmus (small rapid eye movements)
• memory loss

The initial stages of cerebellar atrophy are often characterized by dizziness while walking, lack of coordination in the legs when climbing stairs, and having difficulty judging distances. The middle stage typically involves problems in posture control, slurring speech, writing difficulties, and severe heaviness of the limbs and muscle.

Advanced stages of cerebellar atrophy involves severe intelligence impairment, difficulty swallowing, not being able to sit or stand, and a breakdown in speech or writing communications. Dilantin patients who are concerned over cerebellar atrophy development should talk to their doctors.