Clonic Seizures

By: Brandon Khalil and Natalie L. Boehm, MBA, RBLP-T

Photo from

What are Clonic seizures?

Clonic seizures are the repetitive jerking movements of the muscles in the body. These motor systems can affect the whole body or just specific parts, such as the arms and legs. Clonic seizures are rare and more often occur as a part of a tonic-clonic seizure. Clonic seizures can range from lasting a couple of seconds to a minute.

Generalized vs. Focal Clonic seizures

Clonic seizures may be a generalized or focal onset, depending on the abnormal electrical activity and the area of the brain that is affected. Focal onset clonic seizures cause motor symptoms in a specific part of the body, as it only affects one part of the brain. However, generalized onset clonic seizures affect the whole brain. Additionally, if it is a focal (partial) seizure, the individual can be aware and conscious of what is happening. However, if it is a generalized clonic seizure, the individual may be unconscious.


Symptoms for clonic seizures included stiffening and relaxing of the muscles of the body. Clonic seizures typically affect the neck, face, and arms on both sides of the body. If it is a generalized clonic seizure, the individual may be unconscious. If it is a focal (partial) seizure, the individual is aware and conscious of what is happening. Some individuals may scream and cry out once their seizure begins. In addition, individuals may also have a loss of bowel and bladder control, confusion, fatigue, or a severe headache after a clonic seizure. Doctors should perform EEG testing on an individual whose symptoms do not resemble a clonic seizure, as there could be another underlying neurological problem.

Treatment/Management for Clonic seizures

For individuals with Clonic seizures, it is crucial to protect them from falls to avoid serious injuries. Anticonvulsant medications can help prevent clonic seizures. Common medications prescribed are Depakote, Lamictal, and Topamax. Doctors can order an EEG to find where the abnormal activity is located in the brain causing seizure activity. An EEG diagnosis can help a doctor create a care plan for a patient to help control seizure activity. For those having difficulty getting their seizures under control, doctors may conduct a 3- or 5-day EEG with video to better understand what is happening to the patient during a seizure and how they are affected. Doctors are then able to put together a stronger treatment plan or change treatment altogether.

(Siuly and Yi, 2016).
(Health Research Incorporated, 2018).

An MRI can help doctors find if there is any damage to the brain. Finding areas with scar tissue can help the doctor better understand what is taking place and put together a treatment plan for the patient.  Another treatment that can control clonic seizures is vagus nerve stimulation (VNS). VNS sends pulses of electricity to the vagus nerve, which sends electrical energy into an area of the brain. In detail, VNS stimulates specific brain cells involved in seizures. VNS may help increase blood flow to some brain regions and raise the level of neurotransmitters throughout the body, which is integral to controlling seizures. Studies show that individuals who use VNS have a 28% decrease in seizures within the first three months. In addition, a long-term study done on individuals that used VNS for over ten years showed a decline in seizures by 36% after six months, 58% after four years, and 75% after ten years.

A ketogenic diet can be beneficial in seizure control for children. A ketogenic diet consists of a low-carbohydrate, high-fat diet, which promotes fats as a primary energy source, making ketones. Studies have shown that higher ketone levels have a direct correlation with improved seizure control. Additionally, for half of the children that go on a ketogenic diet, over 50% have seen success in reducing their seizures. In terms of what a Ketogenic diet consists of, the typical ratio used for fats to carbohydrates is 3:1. Therefore, since protein and carbohydrate intake are limited, an individual must plan meals efficiently, accounting for the total number of calories an individual needs a day. Individuals may seek help from a dietician to get a proper meal plan and food list.

(Kemin, 2021)

Seizure first aid for Clonic Seizures

If an individual has a clonic seizure, do not restrain the individual or put anything in their mouth. Individuals may have multiple seizures in a row, so the individual must be in a safe place, clear of debris to prevent fall or further injury. If an individual is not awake and aware, it is essential to lay them on their side to promote better airflow. If a seizure lasts more than five minutes, call 911. Additionally, if an individual’s seizure begins with a fall, assess them for any head injuries and call someone for first aid if necessary. Once individuals are conscious and aware after their seizure, reassure them that they are safe. Also, if they feel tired, confused, or have repeated seizures, stay with the individual until they feel well.


Health Research Incorporated (2018). EEG Brain Function Measurement. Health Research Incorporated. Retrieved from:

John Hopkins Medicine (2021). Tonic and Clonic Seizures. John Hopkins Medicine. Retrieved from:

Kemin (2021). Weighing in on the Keto Diet. Kemin. Retrieved from:

Kiriakopoulos, E. and Osbone-Shafer, P. (2017). Clonic Seizures. Epilepsy Foundation. Retrieved from:

Kossoff, E. (2017). Ketogenic Diet. Epilepsy Foundation. Retrieved from:

Shaffer, P. and Dean, P.  (2018). Vagus Nerve Stimulation. Epilepsy Foundation. Retrieved from:

Shafer, P. (2020). First Aid for Seizures- Stay, Safe, Side. Epilepsy Foundation. Retrieved from:

Sirven, J. and Osborne-Shaffer, P. (2010). Seizure Medication List. Epilepsy Foundation. Retrieved from:

Siuly, S. and Li, Y. (2016). Electroencephalogram (EEG) and Its Background. EEG Signal Analysis and Classification, 3-21. Retrieved from doi: 10.1007/978-3-319-47653-7_1

Read More