Refractory epilepsy is a form of epilepsy that does not respond to treatment with medication. Individuals living with epilepsy experience seizures caused by irregular electrical signals in the brain. Seizures may involve abnormal behavior and movement, episodes of sensory disturbance, or loss of consciousness.

Around 50 million people worldwide live with epilepsy, which experts define as having two or more unprovoked seizures. Typically, doctors use medications to control seizures. But in some individuals, these epilepsy medications are unsuccessful.

Because of this, doctors may use other treatment approaches such as lifestyle changes, vagus nerve stimulation (VNS), or surgery, as opposed to more common epilepsy treatments.

Keep reading to learn more about refractory epilepsy, including its causes, symptoms, and outlook.

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Refractory epilepsy means that medications are not successfully controlling an individual’s epilepsy symptoms.

Refractory epilepsy has several names, including:

  • uncontrolled epilepsy
  • intractable epilepsy
  • drug-resistant epilepsy
  • pharmacoresistant epilepsy

Epilepsy is the fourth most common neurological condition. It causes unpredictable seizures and can contribute to other health issues.

Typically, doctors use anti-epilepsy drugs (AEDs) to control an individual’s seizures. But if an individual has refractory epilepsy, these medications fail to improve the severity or frequency of seizures.

Refractory epilepsy may result from new medication failing to work or medication that was successful in the past no longer working. It can also happen if an individual experiences severe side effects and cannot continue using the medication.

The International League Against Epilepsy (ILAE) wrote in 2010 that it prefers the term “drug-resistant epilepsy” to “refractory epilepsy.”

The ILEA defines the condition based on two points. The first is that the individual has tried at least two AEDs for an adequate amount of time and has failed to become and remain seizure-free. The second is that the individual tolerated the AEDs, and they were appropriate for the individual’s type of seizures.

When AEDs do not work, doctors explore other treatment options to help bring seizures under control.

Doctors do not fully understand the causes of refractory epilepsy, and many reasons may contribute to the condition, including:

  • Incorrect diagnosis: If an individual does not have epilepsy, epilepsy drugs cannot ease their symptoms.
  • Inappropriate treatment: Some epilepsy medications can cause worsening seizure types.
  • Lifestyle factors: Forgetting to take the medication as prescribed or missing doses, sleep deprivation, and alcohol consumption can impact how well seizure medication works.
  • Seizures do not respond: Despite a correct diagnosis and appropriate treatment, sometimes seizures do not respond as expected.

A 2000 study looked at refractory epilepsy in 525 participants. The researchers found that individuals who had several seizures before starting treatment with more likely to develop refractory epilepsy. These findings highlight the importance of seeking early medical intervention when individuals first develop epilepsy symptoms.

The symptoms of refractory epilepsy are continuing epileptic seizures even while using AEDs. There are many types of seizures caused by bursts of electrical activity in the brain producing different symptoms.

The symptoms depend on the part of the brain involved and may include:

  • uncontrolled jerking and shaking (clonic)
  • becoming weak or limp (atonic)
  • muscle twitches (myoclonic)
  • loss of awareness
  • staring into space
  • becoming rigid
  • collapsing
  • unusual sensations, such as tingling in the arms or legs or strange tastes and smells

As seizures involve the brain, essentially anything that the brain controls can appear as an epilepsy symptom.

Typically, an individual tries several AEDs before their doctor considers a diagnosis of refractory epilepsy.

The doctor uses the individual’s medical history to help them understand why treatment approaches have not succeeded in controlling the seizures. They may ask questions about how seizures began and what happens to the individual when they have a seizure. This information provides critical clues about where seizures originate and how they can best help the individual.

Additional tests can help the doctor better understand the individuals’ seizures and why they are challenging to control. These may include an EEG to measure the brain’s electrical activity, and imaging such as CT or MRI scans to indicate where seizures occur in the brain.

Doctors use single or combination treatments with AEDs as a first-line treatment to manage an individual’s seizures. According to the Epilepsy Foundation in 2010, these may include:

  • sodium valproate
  • gabapentin
  • lamotrigine
  • zonisamide
  • levetiracetam
  • carbamazepine
  • topiramate
  • lacosamide

If the initial AED does not work, the doctor may recommend an alternative medication. But if two AEDs are unsuccessful, it is unlikely that other medications will control seizures.

In the 2000 study of refractory epilepsy in 525 individuals, the seizure-free rates of those using their first AED were almost 70%. But for individuals using their second AED, the rate dropped to just 23%. In addition, the researchers reported that none of the five individuals receiving their third AED were seizure-free.

This could be because of how an individual’s body and brain react to and interact with the medications.

Doctors may recommend other treatment options such as dietary changes, VNS therapy, and surgery in these cases.

Dietary changes

The ketogenic diet may reduce seizures in some people. The diet consists of a high fat intake with minimal levels of carbohydrates.

A 2013 review looked at the therapeutic success of the ketogenic diet in managing seizures in children that were uncontrolled by medication. The researchers found that diet successfully controlled seizures in 58.4% of cases.

Vagus nerve stimulation (VNS)

The Food and Drug Administration (FDA) approves VNS to treat refractory epilepsy, reducing the frequency and severity of seizures.

VNS therapy involves using a small electrical device implanted under the skin of the chest to send electrical impulses through the vagus nerve to the brain.

Learn more about VNS here.

Responsive nerve stimulation and deep brain stimulation

Responsive nerve stimulation and deep brain stimulation may also help treat refractory epilepsy.

Like VNS, these treatments also involve neuromodulation devices. These devices, like in VNS, send electrical signals to alter the nerves, releasing substances that change how the cells act, or return them to their correct state.

If an individual has seizures that originate in a clearly identifiable area of the brain, a doctor may recommend removing that part of the brain to control seizures.

The success of the surgery varies depending on the area of the brain involved. For example, individuals with seizures originating in the temporal lobe have up to a 70% chance of becoming seizure-free following surgery.

Learn more about epilepsy surgery here.

The outlook for refractory epilepsy varies, with around 1 in 3 individuals unable to control their symptoms with medication.

Although living with epilepsy without seizure relief from medication may feel highly challenging, it is possible to find a successful treatment. That said, only around 5% of individuals with refractory epilepsy recover completely.

Individuals with refractory epilepsy should work closely with their doctor to minimize the impact of seizures on their life.

It’s important to consider that researchers are developing new treatments and therapies all the time, which could ease an individual’s symptoms and allow them to manage their seizures better in the future.

Refractory epilepsy means that doctors cannot control an individual’s seizures using AEDs. But it is possible that using an alternative AED could manage a person’s symptoms.

If individuals have no success with AEDs, their doctor may recommend other treatment options. These include lifestyle changes, such as dietary changes, VNS, or surgery.

If individuals experience seizures, they should talk with their doctor as soon as possible. Evidence suggests that the earlier someone begins treatment, the more likely it is to control seizures successfully.