The FDA recently announced changes in the labeling of ezogabine (Potiga – GSK/Valeant) to warn about the risks of retinal abnormalities, possible vision loss, and bluish skin discoloration, all of which could be permanent.1

Ezogabine was approved in 2011 for adjunctive treatment of partial-onset seizures in adults.2 The FDA first warned about these risks in April 2013.3 At that time, skin discoloration had developed in 38 of an estimated 605 patients (6.3%) who had taken the drug (most for ≥2 years) in various studies. Retinal pigment abnormalities were found in 11 of 36 patients who had eye examinations; some of these patients had impaired visual acuity, but baseline visual acuity assessments were not available.

The new label recommends limiting the use of ezogabine to patients who have not responded adequately to several alternative antiepileptic drugs. Patients taking the drug should have a baseline eye exam and follow-up exams every 6 months.

1. FDA Drug Safety Communication: FDA approves label changes for anti-seizure drug Potiga (ezogabine) describing risk of retinal abnormalities, potential vision loss, and skin discoloration. Available at www.fda.gov. Accessed November 18, 2013.

2. Ezogabine (Potiga) for epilepsy. Med Lett Drugs Ther 2012; 54:65.

3. FDA Drug Safety Communication: Anti-seizure drug Potiga (ezogabine) linked to retinal abnormalities and blue skin discoloration. Available at www.fda.gov. Accessed November 18, 2013.

Download complete U.S. English article

Treatment of epilepsy should begin with a single drug, increasing the dosage gradually until seizures are controlled or adverse effects become unacceptable. If seizures persist, expert clinicians generally prescribe at least one and sometimes a second alternative drug as monotherapy before considering use of two drugs at the same time. When used for the appropriate seizure type, antiepileptic drugs are roughly equivalent in efficacy. The choice of drug is usually based on factors such as ease of use, adverse effects, interactions with other drugs, presence of comorbid conditions and cost.

The FDA has approved ezogabine (ee-ZOE-ga-been; Potiga – GSK/Valeant) for oral adjunctive treatment of partial-onset seizures in adults. Ezogabine is available in Europe as retigabine (Trobalt).