Studies suggest that Dilantin therapy side effects may include cerebellar atrophy, a degenerative neurological condition affecting the cerebellum.

Dilantin (phenytoin) is a drug commonly prescribed to prevent grand mal seizures and partial complex seizures in patients. The medication may be prescribed to epilepsy patients who experience regular seizures or to brain surgery patients to prevent any seizures they may experience before or after their surgery. However, some patients report troubling Dilantin therapy side effects. 

Dilantin has additional approved uses such as the treatment of mental health conditions. Dilantin is approved to treat a variety of these conditions including anxiety, depression, bipolar disorder, aggressive behavior, Tourette’s syndrome, and ADHD. However, seizure prevention remains the most common use of Dilantin.

The drug works to prevent seizures by stabilizing the brain’s response to stimuli such as flashing lights, which are common triggers for patients with seizures. Although the drug is effective in the treatment and prevention of seizures, Dilantin therapy side effects may outweigh the efficacy of the drug.

Scientific evidence suggests that Dilantin therapy side effects may include cerebellar atrophy, a degenerative neurological condition which targets the cerebellum. Typically, cerebellar atrophy is caused by a variety of neurological conditions or injuries including brain damage, stroke, multiple sclerosis, tumors, seizures, and cerebellar disorders.

When a cerebellum is healthy, the neurological structure helps to create smooth motion, steady balance, coordination, and speech. However, if the cerebellum is damaged by cerebellar atrophy, the neurological connections in the round structure deteriorate. This can cause symptoms similar to those of a stroke, including lack of balance, slow movements, lurching or an unsteady walk, tremors, shaking, unstable eye movements, slurred or slow speech, and memory loss.

Scientists do not yet understand why cerebellar atrophy is among Dilantin therapy side effects, but decades worth of studies support the theory.

The first studies regarding Dilantin therapy side effects were conducted in the 1990s. In 1994, one study aimed to investigate cerebellar atrophy as a potential side effect while also considering that seizures, which Dilantin is prescribed to treat, can also cause the condition. Even when the data from the study was processed to consider cerebellar damage from seizures, the data showed that cerebellar atrophy was more common in patients taking Dilantin.

Further studies have provided more information regarding Dilantin therapy side effects, including which groups it affects and at what drug serum levels.

One scientific study was conducted to evaluate which patients were affected by Dilantin therapy side effects. The study showed that cerebellar atrophy does not only occur in adults treated with the drug but can also occur in children.

Another study was conducted to evaluate drug serum levels in relation to the development of Dilantin therapy side effects. This study showed that cerebellar atrophy was more common when drug serum levels were outside of the recommended therapeutic range. However, the condition has been shown to develop even when drug serum levels were inside the recommended therapeutic range.

Many patients who develop Dilantin therapy side effects are able to recover after discontinuing the drug. However, some patients do experience prolonged symptoms, including a persistent lack of muscle coordination.

If you are concerned that you may be experiencing Dilantin therapy side effects, speak with your doctor before making any changes to your medication.