Generalized tonic–clonic seizure

Generalized tonic–clonic seizure (GTCS), also known as a grand mal seizure, is a type of generalized seizure that affects the entire brain. GTCS is the most commonly recognized form of epileptic seizures and is characterized by a sudden loss of consciousness followed by stiffening of the body (tonic phase) and then jerking of the limbs (clonic phase).

Causes

The causes of generalized tonic–clonic seizures are diverse and can include genetic predisposition, brain injury, infections affecting the brain such as meningitis, metabolic disorders, and exposure to toxins. In many cases, the exact cause remains unknown, a condition referred to as idiopathic epilepsy.

Symptoms

A GTCS typically begins with the tonic phase, where the person loses consciousness and their muscles suddenly contract, causing them to fall if standing. This phase usually lasts about 10 to 20 seconds. Following this, the clonic phase begins, characterized by rhythmic jerking movements of the limbs. This phase can last from less than a minute to several minutes. Other symptoms may include cyanosis (bluish discoloration of the skin due to lack of oxygen), biting of the tongue, and loss of bladder or bowel control. After the seizure, the person may experience confusion, drowsiness, headache, and memory problems, a period known as the postictal state.

Diagnosis

Diagnosis of generalized tonic–clonic seizures primarily involves taking a detailed medical history and performing a neurological examination. Electroencephalography (EEG) is a key diagnostic tool that measures electrical activity in the brain and can help identify patterns typical of epilepsy. Imaging tests such as MRI and CT scans may be used to look for structural causes of seizures.

Treatment

Treatment for GTCS often involves the use of anti-epileptic drugs (AEDs) to control seizures. The choice of medication depends on several factors, including the type of seizures, the patient's age, potential side effects, and whether the patient is pregnant or planning to become pregnant. In some cases, surgery may be an option if medication does not effectively control the seizures. Other treatments include vagus nerve stimulation (VNS), ketogenic diet, and epilepsy surgery.

Prognosis

The prognosis for individuals with generalized tonic–clonic seizures varies. Some people may achieve good control of their seizures with medication and lead normal lives, while others may continue to experience seizures despite treatment. Ongoing research is focused on better understanding the underlying mechanisms of epilepsy and developing more effective treatments.

Prevention

Preventing generalized tonic–clonic seizures involves managing risk factors where possible, such as avoiding head injuries and controlling infections. For individuals with epilepsy, adherence to prescribed treatment plans and lifestyle adjustments to minimize seizure triggers are crucial.