Phenytoin Sodium possible cause of cerebellar atrophy reactions are not balanced against the risk with untreated illnesses especially considering 70 years of Adverse Reactions scientific data. Often other medication options are not even given to the patient.

Even though

The most common manifestations can be the Central Nervous System: encountered with phenytoin
therapy are referable to this system and are usually dose-related.

These include nystagmus,
ataxia, slurred speech, decreased coordination, and mental confusion.

Phenytoin has been shown to metabolize slowly which can cause Cerebellar atrophy

Phenytoin sodium is an antiepileptic drug.

Phenytoin sodium is related to the barbiturates in chemical structure, but has a five-membered ring.

The chemical name is sodium 5, 5-diphenyl-2, 4-imidazolidinedione

Has Phenytoin been properly monitored?

Central Nervous System
Serum levels of phenytoin sustained above the optimal range may produce confusional states referred to as “delirium”, “psychosis” or “encephalopathy”, or rarely irreversible cerebellar dysfunction and/or cerebellar atrophy.

Accordingly, at the first sign of acute toxicity, serum drug level determinations are recommended.

Dose reduction of phenytoin therapy is indicated if serum levels are excessive; if symptoms persist, termination of phenytoin therapy is
recommended (see ACTION AND CLINICAL PHARMACOLOGY, PharmacokineticsAbsorption; WARNINGS AND PRECAUTIONS, General).