Ezogabine, which is known as retigabine in Europe, is a unique anticonvulsant used largely as an adjunctive agent in the treatment of partial seizures. Therapy with ezogabine has not been associated with serum aminotransferase elevations, and clinically apparent liver injury from ezogabine has yet to be reported and must be rare, if it occurs at all.


Ezogabine (e zog' a been) is an anticonvulsant with a unique mechanism of action, decreasing excitability and seizure activity by opening voltage-gated potassium channels in the brain. Ezogabine has been shown to be effective both as monotherapy and in combination with other anticonvulsants for partial seizures. Ezogabine was approved for use in the United States in 2011 and current indications are as adjunctive therapy for partial seizures. Ezogabine is available in tablets of 50, 200, 300 and 400 mg under the brand name Potiga in the United States and Trobalt in Europe and elsewhere. The recommended initial dose in adults is 100 mg three times daily, which can be increased to 200 to 400 mg three times daily. The dose should be increased and tapered gradually. The most common side effects are dose related and include dizziness, somnolence, impaired concentration, nervousness, headache, fatigue nausea, weakness and tremor. Long term therapy has been associated with urinary retention and blue discoloration of the skin, lips, sclera and retina. Rare, but potentially severe adverse events include psychiatric symptoms such as confusion and hallucination and decrease in visual acuity as a result of retinal pigmentation.


Limited data are available on the hepatotoxicity of ezogabine. In clinical trials, therapy with ezogabine was not associated with an increased frequency of serum aminotransferase elevations as compared to placebo treatment, and there were no instances of clinically apparent liver injury. No individual case reports of ezogabine hepatotoxicity have been published since its more wide spread clinical availability. Thus, clinically apparent liver injury due to ezogabine must be rare, if it occurs at all.

Likelihood score: E (unlikely cause of clinically apparent liver injury).

Mechanism of Injury

Ezogabine is extensively metabolized by the liver, largely by glucuronidation and acetylation. However, its metabolism is independent of microsomal P450 system and it has no effect on P450 activity and lacks significant drug-drug interactions.

Drug Class: Anticonvulsants



Ezogabine – Potiga®




Product labeling at DailyMed, National Library of Medicine, NIH



References updated: 18 February 2018

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