17.8 : 抗てんかん薬：カリウムチャネル活性化剤

The Antiepileptic drug ezogabine functions as a potassium channel activator by enhancing transmembrane potassium currents mediated by the KCNQ subtype of potassium channels.

This action stabilizes the resting membrane potential, subsequently reducing neuronal excitability and inhibiting seizures.

Ezogabine is FDA-approved as an adjunctive treatment for focal-onset seizures in patients aged 18 years and older.

It is administered orally and exhibits rapid absorption upon administration.

It undergoes metabolism primarily through glucuronidation and acetylation, with a half-life of 7–11 hours.

Both the drug and its metabolites are excreted via urine.

Common adverse effects include dizziness, drowsiness, fatigue, confusion, and blurred vision.

Additional potential side effects include vertigo, diplopia, memory impairment, and neuropsychiatric symptoms, such as suicidal thoughts and behavior.

Notably, the FDA has issued warnings regarding retinal abnormalities and blue discoloration risks. These effects, along with its limited usage, led to ezogabine's   withdrawal in 2017.