1. Aschenbrenner, Diane S. MS, RN


* Ezogabine (Potiga), the first neuronal potassium channel opener, has been approved for the treatment of partial seizures in adults.


* Precautions are necessary because it can produce urinary retention, QT interval prolongation, or increased suicidal ideation or behaviors.


* Ezogabine can also produce a variety of adverse central nervous system effects.



Article Content

Ezogabine (Potiga), the first in a new drug class known as the neuronal potassium channel openers, has been approved for the treatment of partial seizures in adults; it's considered adjunct therapy to other antiepileptic treatment. Partial seizures are the most common type of seizure. They're created by a disturbance or excessive activity in a limited or localized area of the brain. Ezogabine appears to create its therapeutic effect by keeping the neuronal potassium channels open, stabilizing the resting membrane potential, thereby reducing excitability of the brain cells.


Ezogabine is administered orally three times per day, with or without food. The dosage should be titrated upward in weekly intervals from 300 mg per day initially to between 600 and 1200 mg per day. In patients discontinuing the drug, it should be gradually titrated downward over at least three weeks to prevent withdrawal seizures. Smaller daily dosages are needed in older adults and those with moderate-to-severe renal and hepatic impairment.


Ezogabine use is associated with several serious adverse effects. One of the possible complications, urinary retention, is unique to ezogabine among the antiepileptics. The drug can also prolong the QT interval, and patients taking other drugs known to lengthen the QT interval are at particular risk for complications. Like all antiepileptics, ezogabine carries a warning that it can increase suicidal ideation and behaviors. The most common adverse effects are central nervous system effects (such as dizziness, somnolence, memory impairment, abnormal coordination and balance, and disturbances in attention), ophthalmologic problems like diplopia or blurred vision, and fatigue.


Before a patient begins ezogabine therapy, a thorough assessment of concurrent drug therapy should be made, with special attention paid to medications that can prolong the QT interval. The patient should also be closely monitored for signs of urinary retention. Nurses caring for patients prescribed ezogabine should teach the patient and family about its possible adverse effects and instruct patients who experience urinary hesitancy, difficulty starting a stream, painful urination, or difficulty voiding to contact their health care provider and seek medical attention.