A seizure is a sudden, abnormal electrical activity in the brain that can cause changes in behavior, movements, and consciousness. Seizures can vary in severity and duration, and can be classified into different types based on their characteristics and underlying causes.

Some common types of seizures include:

• Generalized seizures: These seizures involve abnormal electrical activity in both sides of the brain and can cause loss of consciousness, muscle rigidity, and convulsions.
• Focal seizures: These seizures involve abnormal electrical activity in one area of the brain and can cause localized symptoms such as twitching, numbness, or hallucinations.
• Absence seizures: These seizures are brief and can cause a person to stare into space or experience a brief loss of consciousness.

Seizures can be caused by a variety of factors, including epilepsy, head injuries, infections, brain tumors, drug or alcohol withdrawal, and genetic disorders. Treatment for seizures depends on the underlying cause and may include medications to control seizure activity, surgery to remove brain abnormalities, or lifestyle changes to avoid triggers.

If someone experiences a seizure, it is important to ensure their safety by removing any hazards from their immediate environment and protecting their head with a cushion or soft object. After the seizure, medical attention may be necessary to evaluate the cause and provide appropriate treatment.

Nerve cells (neurons) in the brain create, send and receive electrical impulses, which allow the brain's nerve cells to communicate. Anything that disrupts these communication pathways can lead to a seizure. Some types of seizure disorders may be caused by genetic mutations.

The most common cause of seizures is epilepsy. But not every person who has a seizure has epilepsy. Sometimes seizures may be caused or triggered by:

• High fever, which can be associated with an infection such as meningitis
• Lack of sleep
• Flashing lights, moving patterns or other visual stimulants
• Low blood sodium (hyponatremia), which can happen with diuretic therapy
• Medications, such as certain pain relievers, antidepressants or smoking cessation therapies, that lower the seizure threshold
• Head trauma that causes an area of bleeding in the brain
• Abnormalities of the blood vessels in the brain
• Autoimmune disorders, including systemic lupus erythematosus and multiple sclerosis
• Stroke
• Brain tumor
• Use of illegal or recreational drugs, such as amphetamines or cocaine
• Alcohol misuse, during times of withdrawal or extreme intoxication
• COVID-19 virus infection

Not everyone who has one seizure will have another one, and because a seizure can be an isolated incident, your doctor may not decide to start treatment until you've had more than one.

The optimal goal in seizure treatment is to find the best possible therapy to stop seizures, with the fewest side effects.

Medication

Treatment for seizures often involves the use of anti-seizure medications. There are many different options for anti-seizure medication. One of the more recent medications approved by the Food and Drug Administration, cannabidiol (Epidiolex), is derived from marijuana. It's approved to treat certain seizures in children age 2 and older.

The goal of medication is to find the medicine that works best for you and that causes the fewest side effects. In some cases, your doctor might recommend more than one medication.

Finding the right medication and dosage can be complex. You may need to try several different medications to find out which best controls your seizures with the fewest side effects. Side effects may include weight gain, dizziness, fatigue and mood changes. More-serious side effects can cause damage to the liver or bone marrow.

Your doctor will consider your condition, your frequency of seizures, your age and other factors when choosing which medication to prescribe. Your doctor will also review any other medications you may be taking, to ensure that the anti-epileptic medications won't interact with them.

Dietary therapy

Following a diet that's high in fat and very low in carbohydrates, known as a ketogenic diet, can improve seizure control. The ketogenic diet is very strict and can be challenging to follow, as there is a limited range of foods allowed. Variations on a high-fat, low-carbohydrate diet, such as the low glycemic index and modified Atkins diets, though less effective, aren't as restrictive as the ketogenic diet and may provide benefit. These modified diets are still being studied.

Surgery

If other treatments aren't effective, surgery may be an option. The goal of surgery is to stop seizures from happening. Surgery works best for people who have seizures that always originate in the same place in the brain. There are several types of surgery, including:

• Lobectomy (lesionectomy). Surgeons locate and remove the area of your brain where seizures begin.
• Multiple subpial transection. This type of surgery involves making several cuts in areas of the brain to prevent seizures. It's usually done when the area of the brain where seizures start can't be safely removed.
• Corpus callosotomy. This surgery cuts the network of connections between the neurons of the right and left halves of the brain. This is used to treat seizures that start in one half of the brain and travel to the other half. However, even after surgery, seizures may still occur on the side of the brain where they started.
• Hemispherectomy (hemispherotomy). This surgery removes half of the outer layer of the brain. This is an extreme type of surgery that is only used when medications aren't effective in managing seizures and seizures affect only half of the brain. Many daily functional abilities may be lost after this surgery, but children can often recover those abilities with significant rehabilitation.
• Thermal ablation (laser interstitial thermal therapy). This less invasive surgical procedure focuses highly concentrated energy at a specific target in the brain where seizures begin and destroys the brain cells that cause seizures.

Electrical stimulation

Other procedures that may offer seizure relief include:

• Vagus nerve stimulation. A device implanted underneath the skin of your chest stimulates the vagus nerve in your neck, sending signals to your brain that inhibit seizures. With vagus nerve stimulation, you may still need to take medication, but you may be able to lower the dose.
• Responsive neurostimulation. During responsive neurostimulation, a device implanted on the surface of your brain or within brain tissue can detect seizure activity and deliver an electrical stimulation to the detected area to stop the seizure.
• Deep brain stimulation. Doctors implant electrodes within certain areas of your brain to produce electrical impulses that regulate abnormal brain activity. The electrodes attach to a pacemaker-like device placed under the skin of your chest, which controls the amount of stimulation produced.

Pregnancy and seizures

Women who've had previous seizures typically are able to have healthy pregnancies. Birth defects related to certain medications can sometimes occur.

In particular, valproic acid — one possible medication for generalized seizures — has been associated with cognitive deficits and neural tube defects, such as spina bifida. The American Academy of Neurology recommends that women avoid using valproic acid during pregnancy because of risks to their babies. Discuss these risks with your doctor. Because of the risk of birth defects and because pregnancy can alter medication levels, preconception planning is particularly important for women who've had seizures.

In some cases, it may be appropriate to change the dose of seizure medication before or during pregnancy. Women should work closely with their doctors before becoming pregnant with the goal of being on the lowest necessary dose of the safest seizure medication that is effective for seizure control.

Contraception and anti-seizure medications

Some anti-seizure medications can alter the effectiveness of birth control (oral contraceptive) medication. If contraception is a high priority, check with your doctor to evaluate whether your medication interacts with your oral contraceptive, and if other forms of contraception need to be considered.