Tonic-clonic seizure

Tonic-clonic seizure, previously known as a grand mal seizure, is a type of generalized seizure that affects the entire brain. Tonic-clonic seizures are the most commonly recognized type of seizure, characterized by a sudden loss of consciousness, muscle stiffening (tonic phase), followed by rhythmic muscle contractions (clonic phase). These seizures are often associated with epilepsy, but can also be triggered by other health conditions, including low blood sugar, electrolyte imbalances, and brain infections.

Symptoms and Phases

Tonic-clonic seizures are divided into two phases: the tonic phase and the clonic phase.

Tonic Phase

The tonic phase is the initial part of the seizure, typically lasting 10 to 20 seconds. During this phase, the muscles suddenly contract, causing the person to fall to the ground if they are standing. The arms and legs are extended, and the back is arched. Breathing may become irregular or stop, leading to a bluish color of the skin.

Clonic Phase

Following the tonic phase is the clonic phase, which lasts for several minutes. During this phase, the body experiences rhythmic muscle contractions, causing jerking movements. The person may bite their tongue or cheek and may lose control of their bladder or bowels. Breathing becomes irregular, and foam may appear at the mouth.

Causes

Tonic-clonic seizures can have various causes, including:

• Genetic predisposition to seizures or epilepsy
• Brain injury or trauma
• Infections such as meningitis or encephalitis
• Stroke or tumors affecting the brain
• Drug abuse or withdrawal
• Metabolic disorders

Diagnosis

Diagnosis of tonic-clonic seizures involves a thorough medical history and physical examination, along with diagnostic tests such as:

• Electroencephalogram (EEG) to measure electrical activity in the brain
• Magnetic Resonance Imaging (MRI) or Computed Tomography (CT) scan to look for structural abnormalities in the brain
• Blood tests to identify metabolic or genetic conditions

Treatment

Treatment for tonic-clonic seizures focuses on preventing future seizures and may include:

• Antiepileptic drugs (AEDs) to control seizures
• Surgery for cases where seizures are caused by a brain abnormality
• Ketogenic diet or Vagus nerve stimulation (VNS) as alternative treatments

Lifestyle modifications, such as avoiding known seizure triggers, ensuring adequate sleep, and managing stress, are also important in managing seizures.

Prognosis

The prognosis for individuals with tonic-clonic seizures varies depending on the underlying cause. With appropriate treatment and management, many individuals can achieve good seizure control. However, ongoing monitoring and adjustments to treatment may be necessary.

See Also

• Epilepsy
• Status epilepticus
• Partial seizure
• Febrile seizure