Injuries and diseases are the most common causes of seizures. Drug use, birth defects, and genetic conditions may also cause seizures. In adults, however, the causes of seizures are often unidentifiable.
When seizures have a known cause, they are known as nonepileptic seizures. These types of seizures are triggered by an identifiable cause, such as a disorder, injury, or other issue stimulating irregular brain activity. Seizures themselves are not contagious, but they may be caused by an infectious disease, such as AIDS, encephalitis, or meningitis.
Many temporary conditions can trigger seizures. A high fever may cause nonepileptic seizures, particularly in children. This is the most common cause of seizures among patients under age two. Metabolic issues, such as abnormal calcium or glucose levels, are other causes of seizures in babies. Infection, maternal drug use, and lack of oxygen during birth may also be contributing factors to infant seizures.
Recreational drug use, as well as suddenly stopping certain medications, are causes of seizures. Certain prescription drugs can cause seizures as well. Drugs that can trigger seizures include amphetamines, heroine, cocaine, antibiotics, Attention Deficit Disorder treatments, and weight loss drugs. Drinking alcoholic beverages can also induce seizures in some people, particularly if the amount of alcohol ingested is excessive. Alternatively, alcoholics who abruptly cease drinking, and drug addicts who stop taking drugs may experience seizures.
Direct injuries or diseases affecting brain tissue, such as traumatic brain injuries or brain tumors, can also lead to seizures. Patients who experience a stroke are also susceptible to seizures. Other cardiovascular disorders and diseases can stimulate seizures. Failure of other organs in the body, such as the liver or kidneys, has been known to cause seizures in many patients.
Congenital conditions existing from birth are sometimes causes of seizures. Down syndrome can trigger abnormal brain activity. Some other conditions may include neurofibromatosis, Tay-Sachs disease, tuberous sclerosis, and phenylketonuria. Dementia-related diseases that develop late in life, such as Alzheimer's disease, can cause seizures as well. Trauma is an additional cause of seizures in elderly patients.
If no identifiable cause of a seizure is present, the seizure is considered an epileptic seizure. This type of seizure, sometimes called a fit, often occurs repeatedly in the person experiencing it, sometimes under predictable circumstances. Though no known condition triggers the seizures, their existence itself is called a seizure disorder, or simply epilepsy. Scientists postulate that sleep deprivation, electrolyte deficiencies, extreme stress, and many other factors may be associated with epilepsy.