INTRODUCTION
Two new antiepileptic drugs (AEDs) have had recent FDA approval. The first medication to be discussed is clobazam (band name = Onfi). This drug is currently available. The second AED is ezogabine (brand name = Potiga). Ezogabine is not yet available in pharmacies, but should be available soon.
The purpose of this article is to provide educational information on these medications. Please note- for specific treatment with these AEDs, please discuss with your clinician.
CLOBAZAM (BRAND NAME = ONFI)
What kind of medication is Onfi?
Onfi is an AED. It works by binding to GABA receptors in the brain. By binding to GABA receptors, seizure activity is reduced. Onfi fits into the class of drugs known as benzodiazepines. Other benzodiazepines that you may have heard of: lorazepam (brand name = Ativan) and diazepam(brand name =valium).
What types of seizures does Onfi help?
Works on seizures seen in patients with Lennox-Gastaut Syndrome (LGS). LGS seizures can be very severe. Seizure types associated with LGS:
- Generalized tonic-clonic seizure: Old terminology is “grand mal seizure.” This is probably the most recognizable seizure type- patient will collapse to the ground, body will stiffen, full body shaking activity is seen.
- Atypical absence seizure: Old terminology is “petit mal seizure.” Patient will stare and be unresponsive.
- Myoclonic seizures: brief jerks of parts of body. For example, brief, sudden and fast jerk of an arm or leg. Can be a single jerk or a series of jerks.
- Atonic seizures: Muscles lose tone- as if all strength in muscles is lost. Can be very sudden in onset. Can result in falls with injury. The reason for the injuries makes sense. If I fall to the ground, I can protect myself by bracing my fall with my arms. With atonic seizures, patients can fall on their face-unable to protect themselves because their muscles are not responding.
- Tonic seizures: Muscles suddenly increase in tone—muscles go stiff. This can be very intense and sudden.This can also result in falling and injury.
Important side effects: sedation/sleepiness, coordination problems, breathing problems, slurred speech, change in behavior- such as aggressive behavior, and nausea. There are other side effects- this is a brief list of some the more common or more important side effects. It is hoped that with slow increases in the medication, side effects can be minimized or not occur.
What happens if I stop Onfi abruptly?
This can lead to withdrawal symptoms. Symptoms of withdrawal include tremor, feeling anxious and possibly seizures.
Common dosing of Onfi:
Start at 5mg once or twice per day. Starting dose and titration depends on weight (children vs adult) and other clinical factors. Can be titrated up to 20mg twice per day in some patients.
EZOGABINE (BRAND NAME = POTIGA)
What kind of medication is Potiga?
Potiga is an AED. It improves seizure control by increasing the current through potassium channels in the brain’s neurons. The increase in flow through this channel reduces the excitability of the brain- this can reduce seizure activity (remember, a seizure is often due to abnormal electricity coming from the brain).
What types of seizures does Potiga help?
It has been approved for use in focal onset seizures. These are seizures that start in one part of the brain, and then propagate. For example, a seizure starting in the temporal lobe would be a focal seizure. Such a seizure may start with an aura- a feeling of nausea, for example. The seizure could then spread to cause confusion and unresponsiveness.
Important side effects: dizziness, sleepiness, inability to empty the bladder, change in cardiac conduction (QT interval lengthening), and change in behavior- including hallucinations. There are other side effects. These are just a sampling of some the important side effects. It is hoped that with slow increases in the medication, side effects can be minimal or not noted at all.
Common dosing of Potiga:
The medication is to be taken three times per day. The goal is to titrate up to a dose of 600mg to 1200mg per day (total daily dose).
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