Bilateral tonic-clonic seizure is a type of seizure that involves the entire body. It is also called grand mal seizure. The terms generalized seizure, convulsion, or epilepsy are most often associated with bilateral tonic-clonic seizures.
Seizures result from overactivity in the brain. Bilateral tonic-clonic seizures may occur in people of any age. They can occur once (single episode). Or, they can occur as part of a repeated, chronic illness (epilepsy). Some seizures are due to psychological problems (psychogenic or non-epileptic).
Many people with generalized bilateral tonic-clonic seizures have one or more symptoms such as:
- Vision, taste, smell, or sensory changes.
- Dizziness before the seizure. This is called an aura.
Some people have a focal seizure (only affecting one part) that becomes a bilateral tonic clonic seizure.
- Biting the cheek or tongue
- Clenched teeth or jaw
- Loss of urine or stool control (incontinence)
- Stopped breathing or difficulty breathing
- Blue skin color
After the seizure, the person may have:
Exams and Tests
The doctor will perform a physical exam. This will include a detailed check of the brain and nervous system.
An EEG (electroencephalogram) will be done to check the electrical activity in the brain. People with seizures often have abnormal electrical activity seen on this test. In some cases, the test shows the area in the brain where the seizures start. The brain may appear normal after a seizure or between seizures.
Blood and urine tests may also be ordered to check for other health problems that may be causing the seizures.
Seizure - tonic-clonic; Seizure - grand mal; Grand mal seizure; Seizure - generalized; Epilepsy - generalized seizure
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Review Date 1/23/2022
Updated by: Joseph V. Campellone, MD, Department of Neurology, Cooper Medical School at Rowan University, Camden, NJ. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.