The Super-Common Causes and Triggers of Epileptic Seizures

by Jennifer Rainey Marquez Health Writer

Why is the very first thing you might ask yourself when you or one of your people is diagnosed with epilepsy. There are a whole host of possible causes for this neurological condition, marked by repeated seizures, and it’s not always easy to suss out the root cause. “For half of patients, we aren’t able to determine why they have epilepsy,” says Jessica Fesler, M.D., a neurologist at the Cleveland Clinic’s Epilepsy Center in Ohio.

Also confounding, seizures can look different from one patient to the next. Though scientists still have loads to learn, here’s what we know about the most prevalent causes of epilepsy and triggers for seizures.

family on the beach

Cause: Genetic Conditions

Genetic factors are responsible for about 30% to 40% of epilepsy cases. In fact, there are hundreds of genes thought to be associated with the condition. Sometimes genetic traits that lead to epilepsy can be passed down through family members; if a parent or sibling has epilepsy, you’re more likely to have it, too. Still, experts note that genetic and environmental factors often overlap, meaning even if you inherit a predisposition for seizures, you might not develop epilepsy unless the conditions are right.

Cause: Developmental Issues or Prenatal Injury

In children, epilepsy can result from problems with the way the brain is formed in the womb. One abnormality that can be present from birth is focal cortical dysplasia, which Dr. Fesler likens to a scar on the brain. “It occurs when the nerve cells don’t migrate properly as the brain is developing, and it’s a common cause of epilepsy in children.” In other cases, epilepsy may be due to a brain injury that occurs just before or after birth, or a lack of oxygen at birth.

MRI showing blood vessels in brain

Cause: Stroke

Every 40 seconds in the U.S., someone has a stroke, which happens when a blood vessel that feeds the brain becomes blocked or bursts. There’s a reason that strokes are also known as “brain attacks.” The resulting injury can leave a scar in the brain, changing its electrical activity and leading to seizures. Stroke accounts for more than 10% of epilepsy cases in adults, and is the most common cause of epilepsy in those over 60 years old.

Cause: Head Trauma

A traumatic brain injury (TBI) interferes with the brain’s ability to function—sometimes permanently—and can affect thinking, memory, and emotions. In one out of every five people, TBI can also cause what’s known as post-traumatic epilepsy. “Anything that harms or irritates the brain or alters the electrical function of the brain can trigger seizures,” says George Nune, M.D., assistant professor of clinical neurology at University of Southern California’s Keck School of Medicine and medical director of the Keck Hospital epilepsy monitoring unit. These seizures can start immediately after the injury or days, weeks, or months later.

Cause: Brain Tumors

Epilepsy commonly develops in people with brain tumors, and in many cases, it’s a seemingly out-of-nowhere seizure that spurs a patient to get diagnosed. The good news: Research suggests that tumor patients who have seizures tend to fare better than those who don’t. This may be because it prompts the sufferer to get an early diagnosis, or perhaps because seizures are associated with slower-growing tumors and those that are more easily removed by surgery.

Sick woman on couch

Cause: Infection

While you definitely can’t “catch” epilepsy, some infectious diseases that affect the brain or spinal fluid, such as meningitis, can cause seizures, says Emily L. Johnson, M.D., assistant professor of neurology at Johns Hopkins Epilepsy Center. This occurs when an infection breaks the blood-brain barrier, causing swelling and disturbing the brain’s normal functioning. And in little kids, a fever due to infection (such as a cold, flu, or ear infection) can sometimes trigger what’s known as a febrile seizure. Still, only a portion of people who have a seizure while fighting off an infection will go on to develop epilepsy.

Prescription Medication Bottle On Countertop

Seizure Trigger: Prescription Meds

Some commonly prescribed medications, including certain antibiotics, antihistamines, and antidepressants, can lower an epileptic’s threshold for seizures by altering brain activity. “When you’re prescribed a new medication, make sure your doctor or pharmacist knows you have epilepsy or a history of seizures,” says Dr. Nune. “It’s important they check that the drug isn’t likely to provoke seizures in people who are already predisposed.”

woman awake in bed

Seizure Trigger: Stress or Sleep Issues

Oh, the irony: “Some people stress out trying to find a clear trigger for their seizures, but meanwhile stress itself can affect your seizure threshold,” says Dr. Nune. So can lack of sleep. While it’s impossible to eliminate stress from your life—and plenty of people with epilepsy hold demanding jobs—try to find ways to manage your angst in a healthy way, so you’re not mentally scrolling through a list of anxieties at 2 a.m. Taking care of Y.O.U. will also make you less likely to miss a dose of your epilepsy meds (the most common seizure trigger).

Seizure Trigger: Drinking or Drugs

Let’s be clear, knocking back a beer now and then will not produce a seizure. On the other hand, heavy drinking or taking recreational drugs can interfere with anticonvulsant medication and even affect your brain chemistry. In the never-a-good idea category: “You definitely want to avoid stimulants like cocaine, as they can cause seizures even in people without epilepsy,” says Dr. Nunes. Milder stimulants like caffeine are unlikely to trigger seizures, he says, but may keep you up at night, lowering your seizure threshold.

Jennifer Rainey Marquez
Meet Our Writer
Jennifer Rainey Marquez

Jennifer Rainey Marquez is a longtime health and science writer based in Atlanta. Her work has appeared in Women’s Health, O: The Oprah Magazine, Parents, Good Housekeeping, Parade, and many other outlets. You can follow her at @jenrrain.