Alleged Dilantin Side Effects
Patients diagnosed with epilepsy who take Dilantin (phenytoin), a drug to control seizures, may experience side effects on the brain, including a degenerative brain condition known as cerebral or cerebellar atrophy. Dilantin is a broadly prescribed—and one of the most commonly used—anticonvulsant medication used to stop seizures in their early stages.
Dilantin brain side effects are likelier after long-term use and when drug serum levels are beyond the therapeutic range; however, some incidents of cerebellar atrophy have been seen even when Dilantin dosage remained within a normal range. Elderly patients are at greater risk of Dilantin toxicity, placing them at increased risk of brain side effects. Even a small increase in the dose may lead to toxicity. Although reduction or ceasing Dilantin may subside cerebellar atrophy and physical or occupational therapy may sometimes help improve the condition, the condition is often permanent.
Parker Waichman LLP is a national law firm representing numerous clients in drug injury claims. The firm continues to offer free legal consultations to anyone with questions about filing a Dilantin cerebellar atrophy lawsuit.
Cerebellar atrophy is a serious condition that may cause significant changes to a patient’s life and involves the loss of neurons and the connections between neurons in the brain structure called the cerebellum. The cerebellum is a critical part of the brain and controls vital movements like coordination, movement, speech, posture, and balance. In some cases, patients are unable to sit on the edge of a bed without falling due to trunkal ataxia (uncontrollable bobbing of the head or trunk of the body). People with this condition might over-or under-shoot where they intend on positioning their hands, arms, legs, or eyes. Other symptoms may include:
- Clumsiness and fatigue when attempting or performing daily activities
- Cognitive, mood difficulties
- Difficulty with fine motor coordination
- Difficulty walking, maintaining an upright posture
- Nystagmus (small, rapid back and forth eye movements), abnormal eye movements
- Slow, unsteady, jerky movements of the arms or legs, uncoordinated limb or trunk movements
- Slow or slurred speech
- Unsteady gait: Staggering, swaying, stumbling, tripping, or falling when walking
- Visual complaints
Cerebellar atrophy is known as a type of focal cerebral atrophy. The condition causes the loss of brain cells over time. Cerebellar degeneration causes the brain to lose more brain cells, which may lead to significant impairment and various serious and long-lasting health problems. As the cerebellum continues to degenerate, the patient’s symptoms progressively worsen and may include dementia, difficulty speaking, loss of comprehension, loss of reading ability, and seizures. There is no cure to treat cerebral atrophy; therefore, treatment focuses instead on symptoms.
Studies Tying Brain Atrophy to Dilantin
Research and case studies suggest that cerebellar atrophy is a reported side effect of Dilantin for patients who are taking the drug for longer periods of time; however, patients who have taken Dilantin for short periods of time may also develop the brain condition. Patients are also likelier to suffer from Dilantin side effects when a higher dose is taken, especially if taken long-term.
Scientists recognize seizures may cause brain atrophy; however a 1994 study allowed for this when comparing patients who took Dilantin and those who did not. The cerebelli of those treated with Dilantin were much smaller than the same portion of the brain in the non-treated patients. The researchers found that the incidence and severity of cerebellar atrophy was associated to the dose of Dilantin taken.
In a study published in the Indian Journal of Pharmacology entitled “Phenytoin-induced cerebellar atrophy in an epileptic boy who presented with severe cerebellar disorder,” the boy had been taking Dilantin for one decade. He began to steadily recover after withdrawing the medication. Because of this, the researchers note that it is critical to identify symptoms associated with drug toxicity and regularly monitor plasma concentration, accurate dosing, and adherence issues.
Another study entitled “Cerebellar atrophy in patients with long-term phenytoin exposure and epilepsy” published in JAMA Neurology found that cerebellar atrophy was noted in patients with phenytoin exposure. Some researchers have attributed the side effect to seizures; however, others maintain phenytoin is the cause. Prior studies included patients diagnosed with mental retardation and convulsive seizures. This team undertook its case control study in a group of non-retarded patients who were diagnosed with partial epilepsy in a referral population from an epilepsy center to better understand the cause of the cerebellar atrophy. The study involved 36 patients with partial epilepsy and long-term phenytoin exposure. Patients with histories of ethanol abuse, perinatal distress, anoxia, status epilepticus, or neurodegenerative disorders were excluded. Age- and sex-matched controls were selected from a group of healthy volunteers and patients who had undergone magnetic resonance imaging (MRI) for complaints of headache and dizziness; all of the patients and controls underwent MRI testing. A blind review of the MRI scans was conducted and a rating assigned to the degree of cerebellar atrophy. The team found that cerebellar atrophy was significantly more pronounced in patients when compared to controls. A correlation was not found between cerebellar atrophy and seizure severity or degree of phenytoin exposure. The team concluded that cerebellar atrophy may be seen in phenytoin-exposed patients with epilepsy in the absence of generalized tonic-clonic seizures or pre-existent brain damage.
Science Direct published research entitled “Cerebellar volume and long-term use of phenytoin.” The research involved performing MRI cerebellum volumetry in patients exposed to Dilantin and to identify factors tied with cerebellar atrophy. A group of 100 consecutive epilepsy patients who used Dilantin for more than two months and for whom an MRI scan was available for volumetric studies was involved. The researchers studied 56 patients—33 were woman—and the mean age was 33.6 years. The mean duration of epilepsy was 17.6 years and the mean daily dose of Dilantin was 301 mg. Cerebellar atrophy was seen in 20 (35.7 percent) patients and was not tied to frequent, generalized seizures, but did correlate with epilepsy duration and years of treatment with Dilantin and not age and mean daily dosage. A so-called “multiple correlation analysis” and “backward stepwise multiple regression analysis” that included all variables revealed that only duration of treatment was significantly associated with cerebellar atrophy. The team concluded that cerebellar atrophy is frequently associated with long-term Dilantin use and that while duration of epilepsy may have an influence on the disorder, “this is clearly less important than the time of exposure to phenytoin.”
Filing a Dilantin Cerebellar Atrophy Lawsuit
If you or someone you know suffered cerebellar atrophy after taking Dilantin, you may have valuable legal rights. Parker Waichman offers free, no-obligation case evaluations. For more information, contact our firm today by filling out our online form or calling 1-800-YOURLAWYER (1-800-968-7529).