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Seizures: Types, Symptoms, Causes, Diagnosis, and Treatment

Approximately 1 in 10 people may experience a seizure in their lifetime according to statistics from the World Health Organization (WHO) (1). However, it’s important to note that seizure frequency and severity may vary widely among individuals.

What are Seizures?

A seizure refers to a sudden and uncontrolled surge of electrical activity within the brain, leading to alterations in behavior, movements, emotions, and levels of consciousness (2).

During a seizure, the affected brain cells discharge signals in an unregulated manner, resulting in an overload of electrical activity in specific brain regions. This overload might manifest in various symptoms, including abnormal sensations, loss of consciousness, and involuntary muscle movements.

Epilepsy, a condition characterized by recurrent seizures, is diagnosed when a person experiences at least two unprovoked seizures not attributable to any known medical cause or condition.

Types of Seizures

Seizures come in various forms, broadly categorized into focal onset seizures, generalized onset seizures, and seizures with unknown onset.

Focal Onset Seizures

Focal seizures, also known as partial seizures, originate in one specific area of the brain. They may result from various focal injuries that leave scar tissue. These seizures may initiate in one brain region and propagate to others, leading to symptoms of varying intensity (2).

Initially, a person may notice subtle signs known as an aura, which could manifest as altered sensations or a premonition of an impending event. Some describe sensations similar to a rising stomach, which may be similar to a roller coaster ride.

There are two types of focal onset seizures (3):

  • Focal onset impaired awareness seizures: These seizures may lead to unconsciousness, accompanied by automatic behaviors such as lip smacking, chewing, leg movements, or pelvic thrusting. They are also known as complex focal seizures or complex partial seizures.
  • Focal onset aware seizures: Also referred to as simple partial seizures, these occur with the individual remaining awake and conscious during the event, often lasting less than 2 minutes. Their ability to interact with others may or may not be affected.

Generalized-onset Seizures

Generalized-onset seizures involve abnormal nerve discharges spreading throughout the brain’s cortex simultaneously. They often stem from an imbalance in the brain’s inhibitory and excitatory circuits (2).

Factors such as sleep deprivation or excessive alcohol consumption might heighten the risk of generalized-onset seizures, particularly in those genetically susceptible.

Types of Generalized-Onset Seizures include:

  • Tonic-clonic: Characterized by stiffening limbs, temporary cessation of breathing, followed by jerking movements (4).
  • Clonic: Rare, causing jerky movements on both sides of the body, commonly seen in babies.
  • Tonic: Results in stiffened body, arms, and legs, commonly occurring during sleep (5).
  • Myoclonic: Features jerky movements in one or more muscle groups, typically leaving the individual alert (6).
  • Atonic: Involves sudden loss of muscle strength, often leading to falls and potential injuries (7).
  • Infantile spasms: Characterized by sudden stiffening of the body and head dropping forward, often resolving by age 4 but could precede epilepsy later in life (8).
  • Febrile seizures: Convulsions due to high fever, usually harmless and lasting a few minutes (9).

Unknown Onset Seizures

In some instances, seizures may occur without anyone witnessing their onset, such as waking up to find a partner experiencing a seizure (10).

Understanding seizures and their various types might be overwhelming, especially for those experiencing them or caring for someone who does. Remember, seeking support from healthcare professionals and support groups may provide valuable guidance and reassurance on managing seizures effectively.

Symptoms of Seizures

Seizures typically occur at different times rather than simultaneously. It’s noteworthy that a focal seizure may evolve into a generalized seizure, with the progression varying in speed (11).

Prior to the onset of a seizure, individuals may experience warning signs, though these manifestations differ among people. These pre-seizure symptoms might include:

  • A sudden sensation of fear or anxiety
  • Dizziness
  • Alterations in vision
  • Nausea or a sense of queasiness
  • Sensations of detachment from one’s body
  • Headaches
  • Jerky movements of the limbs leading to potential dropping of objects
  • Mood fluctuations
  • Experiencing déjà vu

During the seizure itself, certain signs become apparent, indicating its occurrence. These signs may include:

  • Loss of consciousness followed by confusion
  • Drooling or frothing at the mouth
  • Collapsing or falling
  • Perception of a peculiar taste in the mouth
  • Involuntary muscle spasms
  • Tongue biting
  • Teeth clenching
  • Emitting unusual sounds, like grunts
  • Loss of control over bladder or bowel function
  • Rapid, abrupt eye movements

Experiencing seizures may be distressing and challenging, both for individuals directly affected and their loved ones. If you or someone you care about is dealing with seizures, know that support and medical assistance are available to help navigate through these experiences and improve quality of life.

Causes and Risk Factors of Seizures

Seizures, while commonly associated with epilepsy, might stem from various triggers and conditions. Here are some potential factors that may contribute to seizures:

  • Severe concussion or traumatic brain injury (12)
  • Brain tumors, including cancerous growths (13)
  • Cerebral hypoxia, which occurs due to lack of oxygen reaching the brain (14)
  • Substance abuse, including drugs, alcohol, and even caffeine (15); (16)
  • Withdrawal from drugs or alcohol (17)
  • Aneurysms (18)
  • Electrolyte imbalances, particularly low levels of sodium, calcium, or magnesium (19)
  • Fevers, especially high temperatures, which may lead to febrile seizures, particularly common in children (20)
  • Sensitivity to flashing or flickering lights (21)
  • Eclampsia, a condition related to high blood pressure during pregnancy (22)
  • Hormonal fluctuations, such as in catamenial epilepsy, which correlates with menstrual cycles (23)
  • Infections, including encephalitis or meningitis caused by various pathogens (24)
  • Autoimmune conditions leading to brain inflammation due to attacks from the immune system (25)
  • Genetic disorders inherited from one or both biological parents (26)
  • Structural abnormalities in the brain present from birth (27)
  • Sepsis, a severe infection affecting the whole body (28)
  • Metabolic issues like high or low blood sugar levels (29)
  • Strokes or transient ischemic attacks (TIAs) (30)
  • Psychogenic seizures associated with mental health conditions like conversion disorder (31)
  • Exposure to toxins and poisons like carbon monoxide or heavy metals (32)

It’s important to note that while these factors may contribute to seizures, not everyone exposed to them will necessarily experience seizures. Additionally, individuals may have seizures due to a combination of factors, and the manifestation may vary greatly from person to person.

Understanding the potential triggers and risk factors might help individuals and healthcare providers better manage and treat seizures effectively.

Diagnosis of Seizures

When you visit your healthcare provider concerning seizures, he or she may conduct a thorough evaluation aimed at understanding your specific situation. This typically involves a series of inquiries about your seizure experiences and a neurological examination.

During the assessment, your emotional state will be considered alongside evaluations of your motor skills and cognitive abilities. Subsequently, your healthcare provider may recommend one or more diagnostic tests, which might include:

  • Blood tests or a spinal tap to check for signs of infection (33).
  • Imaging procedures like MRI, CT, or PET scans to identify any potential brain abnormalities (34).
  • Electroencephalography (EEG), where electrodes are placed on your scalp to monitor brain activity (35).
  • Single-photon emission computed tomography (SPECT), a test involving the injection of a small amount of radioactive substance to observe blood flow during seizures (36).

For individuals experiencing frequent seizures, additional testing may be necessary. In such cases, your healthcare provider might suggest more invasive procedures, such as surgery. This may entail inserting electrodes into the brain through small openings in the skull, in order to determine the location where the seizure is coming from.

These measures aim to provide a comprehensive understanding of your condition and guide appropriate management strategies.

Treatment Options for Seizures

If you experience seizures, it’s important to understand that while some individuals may only have one seizure and not require treatment, ongoing seizures may necessitate intervention. Here are several potential treatment options your healthcare provider may recommend:

  • Medication: Anti-seizure medications are commonly prescribed, although it’s essential to recognize that they may carry significant side effects. Your healthcare provider will work with you to explore various medication options, considering effectiveness and minimizing potential side effects. It may require trying different medications before finding the most suitable one (37).
  • Surgery: In cases where seizures originate consistently from a specific area of the brain and a person does not respond to anti-epileptic medication, surgical intervention may be considered. Neurosurgery might involve the precise removal of the affected brain tissue to disrupt seizure activity (38).
  • Vagus Nerve Stimulation: The vagus nerve, extending from the brain to the abdomen, plays a crucial role in regulating various bodily functions, including seizure activity. Vagus nerve stimulation involves the implantation of a device beneath the skin of the chest, which delivers electrical impulses to the brain via the vagus nerve. While this intervention may help reduce seizure frequency, medication may still be necessary (39).
  • Deep Brain Stimulation: Surgeons may also recommend deep brain stimulation, often described as a pacemaker for the brain, wherein devices are implanted in specific brain regions to interrupt abnormal electrical signals and help prevent seizures (40).
  • Responsive Nerve Stimulation: Another option for medication resistant epilepsy, is responsive nerve stimulation, where a device implanted in the brain detects and interrupts seizure activity (41).

It’s crucial to consult with a healthcare professional to determine the most appropriate treatment approach for managing seizures. Each individual’s condition varies, and treatment decisions may be made in consideration of their specific circumstances and medical history.

Seizures vs. Epilepsy: What’s the Difference?

Seizures and epilepsy are often used interchangeably, but it’s important to recognize their distinctions to better understand these neurological events.

There are two main types of seizures based on their triggers (2):

  • Provoked Seizures: These seizures are prompted by external factors that irritate the brain. Triggers may include infections, fluctuations in blood sugar levels, adverse reactions to medications, alcohol withdrawal, sleep deprivation, or exposure to flashing lights.
  • Unprovoked Seizures: These seizures occur without a clear external trigger. If someone experiences two or more unprovoked seizures, they may receive an epilepsy diagnosis. Epilepsy, a neurological disorder, may have genetic roots or result from factors such as head injuries, infections, tumors, or prenatal injuries. Certain developmental conditions like autism may also increase the likelihood of epilepsy.

Additionally, there’s a condition known as Psychogenic Non-Epileptic Seizures (PNES), which manifests with symptoms resembling epileptic seizures. However, PNES differs in that its cause stems from intense emotional trauma or stress rather than abnormal brain activity. It’s noteworthy that an individual may have both PNES and epilepsy concurrently (42).

Understanding these distinctions might aid in proper diagnosis and management of seizures and epilepsy, enhancing patient care and quality of life.

Prevention of Seizures

Seizures might affect anyone at any time, often without warning, making prevention a challenging task. While it’s impossible to guarantee complete avoidance, there are steps you might take to minimize your risk.

Here are some practical tips to help reduce your chances of experiencing a seizure:

  • Use Safety Equipment: Head injuries are a significant cause of seizures. Protect yourself by using appropriate safety gear such as helmets, safety belts, and restraints whenever engaging in activities that pose a risk of injury (43).
  • Address Infections Promptly: Prompt treatment of infections, especially those affecting the eyes and ears, is crucial as untreated infections might spread to the brain and trigger seizures. Be vigilant, particularly during instances of high fever, which might also precipitate seizures (44).
  • Manage Chronic Health Conditions: Proper management of chronic conditions, especially diabetes, might significantly reduce the likelihood of seizures associated with blood sugar fluctuations. Stay diligent in managing your health to minimize seizure risk (45).
  • Practice Responsible Substance Use: Avoiding misuse and abuse of alcohol, prescription drugs, and recreational substances is vital to reduce the risk of seizures. If you’re dependent on these substances, withdrawal may also trigger seizures. This highlights the importance of seeking professional help for substance dependence (46, 47, 48).
  • Identify and Avoid Triggers: Individuals with a history of seizures triggered by specific stimuli, such as flashing lights, should consider taking precautions to avoid similar triggers whenever possible. Awareness of personal triggers might help mitigate seizure occurrences (49).

By incorporating these preventive measures into your lifestyle, you can empower yourself to reduce the risk of experiencing seizures. While complete prevention may not be achievable, proactive steps may enhance your overall well-being and quality of life.

What To Do During A Seizure?

If someone close to you experiences a seizure, there are several steps you may take to offer support. It’s crucial to stay calm during the situation, as there’s no surefire way to halt a seizure once it begins. However, your assistance might make a difference.

The Centers for Disease Control and Prevention (CDC) offer the following guidance (50):

  • Stay by Their Side: Remain with the person throughout the seizure until it concludes or until they regain full consciousness.
  • Check for Medical Bracelet: Look for any medical identification the person might be wearing.
  • Remove Potential Hazards: If feasible, remove items like glasses or neckwear to prevent injury.
  • Guide to Safety: If the person is standing, gently steer them to the floor to prevent falling or harm. If they’re already on the ground, help position them on their side to avoid inhalation of saliva or vomit.
  • Provide Cushioning: If possible, place something soft under their head for added comfort.
  • Avoid Restraint: Refrain from restraining the person during the seizure and avoid placing objects in their mouth.

After the seizure ends, it’s important to:

  • Assess for Injuries: Check the person for any injuries sustained during the seizure.
  • Stay Present: Remain with them until they are fully awake and alert, providing a safe environment for rest.
  • No Food or Drink: Do not offer them food or drink until they are fully conscious and alert.
  • Reposition: Turn them onto their side if they aren’t already in that position and clear their mouth of any fluids.

When to Seek Medical Assistance

While most seizures don’t demand immediate medical attention, there are instances when it’s essential to call for help. Some instances include but are not limited to the following:

  • The seizure persists for over 5 minutes.
  • There are recurrent seizures.
  • The person doesn’t regain consciousness after the seizure.
  • It happens in someone with no prior history of seizures.
  • The seizure occurs in a pregnant individual.

Understanding how to assist someone during a seizure might be vital in ensuring their safety and well-being. By following these guidelines and knowing when to seek professional help, you may provide valuable support to those experiencing seizures.

Remember, staying informed and remaining calm are key components in assisting individuals during such episodes.


Seizures are complex neurological events that may affect people of all ages. While they might be frightening to witness, it’s important to remember that they are often manageable with proper diagnosis and treatment. Understanding the different types of seizures, their causes, and potential triggers might empower you and your loved ones to effectively manage the condition.