16.07.2021 – 13:39
Epilepsy is a neurological disorder that causes recurrent seizures. A seizure is a sudden, abnormal change in the electrical activity of the brain. This causes temporary symptoms such as tremors, loss of consciousness or blank stare.
The first line of treatment is antiepileptic drugs (AEDs). But for some people, AEDs are unable to control their crises. This is known as refractory epilepsy.
Other names for refractory epilepsy include:
In refractory epilepsy, seizures continue even with AED. Understandably, this can be frustrating and stressful.
What is refractory epilepsy?
Refractory epilepsy occurs when AEDs fail to improve the severity or frequency of seizures. It is diagnosed after you have tried at least two AEDs (alone or together) with no positive results.
As a result, the condition is often characterized by frequent medication changes.
Refractory epilepsy can occur in several ways:
You take medication for epilepsy, but it does not work.
Existing drugs, which were used to control seizures, stop working.
You have severe side effects from AED, making it difficult to continue treatment.
How common is refractory epilepsy?
Epilepsy is common. More than 70 million people in the world have it. Of these people, approximately 30 to 40 percent have resistant epilepsy.
Causes of refractory epilepsy
The exact cause of refractory epilepsy is unknown. However, there are some theories:
Pharmacokinetic hypothesis. Flow transporters are proteins that move toxic substances from cells. This hypothesis proposes that flow transporters in organs are overactive and reduce AED levels in the body, which reduces the effectiveness of drugs.
Neural network hypothesis. This theory states that seizures suppress the body’s natural anticancer network and prevent AEDs from reaching the correct neurons.
Hypothesis of internal severity. In this hypothesis, it is stated that severe forms of epilepsy are more resistant to AED.
Gene variant hypothesis. This hypothesis states that genes associated with the transport of AEDs in the body lead to drug resistance.
Target hypothesis. AEDs work by targeting specific pathways and receptors in the brain. This hypothesis states that changes in these goals reduce the effects of drugs.
Carrier Hypothesis. This hypothesis proposes that the flow transporters in the blood-brain barrier are overactive, reducing the amount of drug that enters the brain.
Sometimes, a person’s crises can seem resilient even if they really are not. This is called apparent pharmacoresistance.
In this case, the medication can not control the seizures due to the following reasons:
other medications cause interactions, reducing effectiveness
non-epileptic condition that causes seizures
misdiagnosis of the type of seizure or epilepsy syndrome
lifestyle factors, such as illegal drug use or stress
Symptoms of refractory epilepsy
Refractory epilepsy causes seizures despite taking medication. The symptoms of these crises are the same as with crises in general.
Possible symptoms include:
loss of consciousness
loss of bladder or bowel control
The goal of treatment is to find effective alternative therapies. This may include nerve stimulation, brain surgery or lifestyle changes. Your doctor may also suggest additional medications or different doses.
If AEDs do not improve your seizures, seek referral to a comprehensive epilepsy center where medical professionals have special training in diagnosing and treating refractive epilepsy.
The view is generally better when refractory epilepsy is diagnosed early.