Do you know someone who has had a seizure? Have you had one yourself? According to the World Health Organization, up to 1 in 10 people worldwide will have a seizure at some time in their life. Read on to learn more about the different types of seizures, what causes them, and how they can be treated.
What is a seizure?
Seizures are defined as behavioral or physical changes that happen after abnormal electrical activity in the brain. During a seizure, some people may have uncontrollable changes in the way they move and act. They may also have changes in their level of consciousness. Seizures can last from a few seconds to 15 minutes. If a seizure lasts longer than 5 minutes, or if another seizure starts soon after the first one is over, it is considered a medical emergency.
“During a seizure, a person may look confused or be unresponsive, behave oddly, or lose consciousness. Seizures can also cause part or all of the body to have jerky movements.”
Margaret Frazer, MD
Neurologist and Senior Director at Pfizer Inc.
What are the different types of seizures?
We might think of seizures in the way they’re shown on TV, with the person collapsing to the ground, shaking, and not being aware of what’s happening. However, it’s more common for the person having a seizure to appear confused, stare into space, make unusual movements and be unable to talk or answer questions. Some may experience sensations such as a strange taste or smell, or a “funny feeling” as a warning sign that a seizure may happen.
The fact is, there are many different types of seizures, but they are typically divided into 2 broad categories: generalized seizures and focal seizures (sometimes called partial seizures).
Generalized seizures affect both sides of the brain. A type of generalized seizure, called an absence seizure, is most common in children 4 to 14 years old. They can have a wide range of effects, from rapid blinking and brief periods of staring into space, to loss of consciousness, falls, and muscle spasms.
Focal or partial seizures happen in one area of the brain. Their effects include confusion and unresponsiveness. Some people will have a type of focal seizure that spreads to both sides of the brain and leads to a generalized seizure.
Another type of seizure is called status epilepticus. These are seizures that last longer than 5 minutes or that happen close together without the person recovering between seizures. Status epilepticus requires emergency medical treatment.
What causes seizures?
Seizures happen in more people than many may realize, and they can happen for a number of reasons. Many times the cause is not known. Below are some of the conditions or events that may be associated with seizures in various age groups.
In newborns: Abnormal brain development during pregnancy, lack of oxygen during birth, low levels of blood sugar or certain other chemicals in the blood, certain inherited conditions, bleeding inside the skull, maternal drug use, brain tumors, certain neurodevelopmental conditions.
In infants and children: Fever, infections, brain tumors (rarely).
In children and adults: Birth defects, genetic factors, head injury, progressive brain disease (rarely), brain tumors.
In the elderly: Stroke, Alzheimer’s disease, trauma, brain tumors.
What is the difference between seizures and epilepsy?
A seizure is a brief change in normal brain activity. Having a single seizure does not mean you have epilepsy. Epilepsy is a disorder of the brain that affects about 3.4 million people in the US. A person may be diagnosed with epilepsy if he or she has any of the following:
- At least 2 unprovoked (or reflex) seizures more than 24 hours apart.
- One unprovoked (or reflex) seizure and a 60% or greater likelihood of further seizures after 2 unprovoked (or reflex) seizures, occurring over the next 10 years.
- A diagnosis of an epilepsy syndrome.
How are seizures diagnosed?
If you have even one seizure, tell your healthcare provider about it. He or she may refer you to a neurologist who may run tests to rule out other medical conditions that cause seizures or similar symptoms. These tests may include EEGs (tests that measure electrical activity in the brain), blood and urine tests, head scans, and a lumbar puncture (spinal tap).
Also, be sure to tell your healthcare provider about any other recent symptoms or health concerns. He or she can use this information to determine a possible cause of the seizure and to develop a treatment plan, if necessary.
If someone witnessed your seizure, it is important to gather as much information as you can from him or her and to share as clear a description of the event as possible with your healthcare provider.
How are seizures treated?
Treatments, including anti-seizure medications, surgery, nerve stimulation, and dietary changes, may help stop or lessen seizures, Talk to your healthcare provider about treatment options.
If you would like to learn more about clinical research in epilepsy and seizures or find a clinical trial for yourself or a loved one, visit clinical trials.gov. Examples of search terms include: seizure, generalized seizures, partial seizures, and epilepsy. Be sure to talk with your healthcare provider about clinical trials and whether enrolling in one is right for you.
Margaret Frazer, MD, is a neurologist and Senior Director of Medical Affairs at Pfizer Inc.
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