Known Causes of Seizures in Adults

Seizures are a dramatic manifestation of a serious disturbance in brain activity. A diverse variety of conditions and disorders can precipitate seizure activity in adults. Brain injury, brain swelling and increased pressure on the brain as well as chemical imbalances are common causes of adult seizure activity. Correct diagnosis of the underlying cause leads to appropriate medical intervention to alleviate or control the future occurrence of seizures.

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Epilepsy is a brain disorder in which nerve cells in the brain periodically exhibit abnormally increased electrical activity that provokes a seizure. People are diagnosed with epilepsy when no other condition explains the occurrence of two or more seizures. The Epilepsy Foundation estimates approximately 3 million Americans have epilepsy. According to the National Institute of Neurological Disorders and Stroke, approximately 25 to 30 percent of people with epilepsy continue to have intermittent seizures despite optimal medical treatment 13.


A stroke is a brain injury caused by insufficient blood flow and oxygen delivery to part of the brain. A clot that blocks blood flow leads to an ischemic stroke. A bleeding blood vessel causes a hemorrhagic stroke. In an article titled “Stroke and Seizures,” published electronically by Stroke Awareness for Everyone, neurologist Dr. Maynard Pathak explains that seizures can occur during or shortly after the onset of a stroke 3. Brain swelling and oxygen deprivation are the primary factors that precipitate stroke-associated seizures 3. Notably, people can develop epilepsy months to years after a stroke due to the stroke-related brain injury.

Brain Tumor

The occurrence of new onset seizure activity in an adult may be a symptom of a brain tumor. The American Brain Tumor Association notes approximately one-third of people with a brain tumor are diagnosed after experiencing a seizure 2. The Epilepsy Therapy Project reports brain tumors that often present with new onset seizures include glioblastoma, astrocytomas, meningioma, oligodendroglioma, ganglioglioma and metastatic tumors to the brain caused by cancers elsewhere in the body 4.cause:

  • The Epilepsy Therapy Project reports brain tumors that often present with new onset seizures include glioblastoma
  • astrocytomas
  • meningioma
  • oligodendroglioma
  • ganglioglioma
  • metastatic tumors to the brain caused by cancers elsewhere in the body 4

Traumatic Brain Injury

Traumatic brain injuries due to falls, motor vehicle accidents and blows to the head can cause swelling, bleeding or direct physical trauma to the brain. Any of these brain insults can cause seizures. The Centers for Disease Control and Prevention warns that the occurrence of a seizure after a head injury is a danger sign for severe brain injury.

Metabolic Disturbances

Metabolic disturbances that cause chemical imbalances in the body can precipitate adult seizures. As pointed out by the Mayo Clinic, low blood sugar, or hypoglycemia, is a notable example. Other well-known metabolic disturbances associated with seizures include low blood sodium, elevated blood ammonia associated with severe liver disease, and electrolyte imbalances related to kidney failure. Correction of the underlying metabolic disturbance eliminates seizure activity.