What Are Generalized Tonic-Clonic Seizures?
Generalized tonic-clonic seizures (formerly known as grand mal seizures) are a type of seizure that affects the entire brain. These seizures typically involve a sudden loss of consciousness, followed by muscle stiffening (tonic phase) and rhythmic jerking movements (clonic phase). They are one of the most well-known types of seizures and are often associated with epilepsy.
What Causes Generalized Tonic-Clonic Seizures?
These seizures can result from a variety of causes, including:
- Epilepsy (a chronic condition causing repeated seizures)
- Brain injury or trauma
- Infections such as meningitis or encephalitis
- Brain tumors
- Genetic conditions affecting brain function
- Stroke
- High fever (especially in children – febrile seizures)
- Withdrawal from alcohol or drugs
- Metabolic imbalances like low blood sugar or sodium levels
- Certain medications or drug toxicity
Symptoms of Generalized Tonic-Clonic Seizures
A seizure usually follows a predictable pattern and includes these stages:
- Aura (in some cases) – A strange feeling or warning before the seizure starts
- Tonic phase – Sudden stiffening of the body and loss of consciousness
- Clonic phase – Rhythmic jerking of the arms, legs, and face
- Postictal phase – Confusion, fatigue, or sleepiness after the seizure ends
Other symptoms may include:
- Crying out or groaning
- Loss of bladder or bowel control
- Biting the tongue or inside of the cheek
- Breathing difficulties or turning blue (temporary)
How Are Generalized Tonic-Clonic Seizures Diagnosed?
To diagnose the condition and find the underlying cause, doctors may use:
- Medical history and seizure description
- Neurological exam
- Electroencephalogram (EEG) – to measure brain activity
- Brain imaging – such as MRI or CT scan to detect abnormalities
- Blood tests – to check for infections or metabolic imbalances
- Lumbar puncture (spinal tap) – if infection is suspected
Treatment Options for Generalized Tonic-Clonic Seizures
Treatment is focused on managing seizures and preventing future episodes:
- Antiseizure medications (AEDs) – such as valproate, lamotrigine, or levetiracetam
- Ketogenic diet – a high-fat, low-carb diet may help some people with epilepsy
- Surgery – in rare cases, if seizures do not respond to medications and a specific brain area is involved
- Vagus nerve stimulation (VNS) – a device implanted to reduce seizure frequency
- Lifestyle changes – avoiding triggers like stress, alcohol, and lack of sleep
What to Do If Someone Has a Seizure
- Stay calm and ensure the person is safe
- Turn them onto their side to help breathing
- Remove sharp or dangerous objects nearby
- Do not put anything in their mouth
- Time the seizure – if it lasts more than 5 minutes, seek emergency help
- Stay with them until they are fully awake
Complications of Generalized Tonic-Clonic Seizures
While most seizures resolve on their own, complications may include:
- Injury from falling or hitting objects
- Breathing difficulties during the seizure
- Prolonged seizures (status epilepticus) – a medical emergency
- Emotional or psychological distress
- Memory problems or difficulty focusing
Can Generalized Tonic-Clonic Seizures Be Prevented?
Not all seizures can be prevented, but risk can be lowered by:
- Taking medications regularly and as prescribed
- Getting enough sleep
- Avoiding alcohol or recreational drugs
- Managing stress
- Keeping regular follow-up appointments
Who Is at Risk?
Seizures can affect anyone, but risk increases in those who:
- Have epilepsy or a family history of seizures
- Have had a head injury or stroke
- Are exposed to flashing lights or sleep deprivation
- Use certain medications or substances
- Have metabolic or brain disorders
Living with Generalized Tonic-Clonic Seizures
Many people with these seizures live full, active lives with proper treatment. Helpful management strategies include:
- Regular medication use
- Wearing a medical ID bracelet
- Educating family and friends about seizure first aid
- Avoiding known triggers
- Maintaining a healthy lifestyle
- Seeking support groups or counseling when needed