Can phenytoin prevent Alzheimer's disease?

Alzheimer disease (AD) is the most common neurodegenerative disease presenting with relentless memory loss. A number of factors contribute to comorbidity and mortality and seizures are among the most common ones. Seizures worsen existing demantia, and by causing falls lead to serious complications like fractures and intracranial hemorrhage. Hippocampus is one of the earliest affected structures in brain in AD. It undergoes atrophy followed by progressive neuron loss. Atrophy appears much before the clinical manifestations of AD develop. Hence, there is a potential for its prevention or reversal. Neuron loss in brains of AD have two important consequences: these include development of AD and seizures. Patients of AD have unusually high incidence of seizures and the first seizure episode in this population is considered to be an indication of treatment with anti-seizure drugs. Among many drugs that have been shown to prevent hippocampal atrophy is phenytoin. It is time tested and proven anticonvulsant that can be used to prevent the development of atrophy and consequent development of AD. Phenytoin can thus be exploited for its dual effects i.e. reversal of hippocampal atrophy and anti-seizure effects. Selection of patients, appropriate dose, duration, monitoring and drug safety are important issues to be addressed before the testing of this hypothesis can be considered. Ideal candidates will be those who are at risk of development of AD or those with milder symptoms.