Grand mal seizure

Medical quality assurance by Dr. Albrecht Nonnenmacher, MD at June 22, 2016
StartDiseasesGrand mal seizure

Grand mal seizures, also known as tonic-clonic seizures or generalized tonic-clonic seizures are the most common form of generalized seizure. Caused by abnormal electric activity in segments of the brain, grand mal seizures feature rhythmic, jerking muscle contractions; probable loss of consciousness; and stiffening or tension in the extremities. These seizures are the most recognizable in the generalized seizure family, and they can be caused by many health issues including epilepsy.


Definition & Facts

Grand mal seizures are the most common of the six major types of generalized seizures. The others are absence seizure, myoclonic seizure, clonic seizure, tonic seizure, and atonic seizure. Grand mal seizures are also called clonic-tonic seizures because they combine and synthesize the characteristics of clonic and tonic type seizures: jerking muscle movements and muscle stiffness.

These stages occur rapidly, one after the other, and are followed by the postictal phase, in which the patient falls into a deep sleep due to physical and mental exhaustion. Seizures can also be partial, meaning that they are caused by electric triggers from a small section of the brain rather than triggers throughout the brain, as is the case with generalized seizures.

Symptoms & Complaints

There are many signs and symptoms that imply the presence or occurrence of a grand mal seizure, but not all of them happen in each individual case. Grand mal seizures are characterized by the presence of two distinct phases: the tonic phase, during which patients lose consciousness, often fall down, and experience intense muscle contractions; and the clonic phase, in which muscles alternately flex and relax for between one and five minutes in most cases.

People experiencing a grand mal seizure may exhibit varied symptoms, such as screaming or crying due to seizing vocal chords and incontinence or loss of bowel and bladder control. After the seizure has ended, most patients will be temporarily unresponsive, extremely confused or dazed, and in possession of a massive series of headaches.

Before the onset of a seizure, many people will have a type of premonition or uneasy feeling; this medically observed condition is called an aura, and it may include feelings of numbness or dread throughout the body and the sensation of a strange smell.


In many cases, grand mal seizures are idiopathic, meaning that their origin is spontaneous and that they could occur because of chemical or neurological imbalances or a genetically determined seizure threshold. This seizure threshold can be lowered by any number of extenuating physical or mental circumstances, including fatigue, stress, malnutrition, and anxiety. In any case, the brain's normal electronic system for communication is disrupted, and electrical and chemical transmissions across the synapses are disturbed.

Patients may also have a genetic disorder or a seizure disorder such as epilepsy that predisposes them toward seizures. More often, grand mal seizures are caused by underlying health problems, including traumatic head injuries, oxygen-deprivation injuries or conditions, or stroke.

A medical history of disease, including susceptibility to meningitis or other infections, previous brain tumors, or drug abuse and withdrawal patterns, can also lead to grand mal seizures in many people. Severe withdrawal from alcohol can trigger generalized or partial seizures in patients. 

Diagnosis & Tests

The doctor must rely heavily on the testimony of people who witnessed the seizure to be able to properly diagnose the underlying condition. If the doctor is able to identify a particular trigger, such as flashing lights or loud music, the seizure can be much more easily classified. An in-depth medical interview will also determine whether anxiety, lack or sleep, or other risk factors could have contributed to the seizure. 

If questioning and risk factor analysis do not turn up any obvious answers, the doctor will subject the patient to a thorough neurological examination that tests muscle condition and motor symptoms. The exam also often includes questions to test patient memory, recall, judgment and capability for critical thought.

After these tests, other tests can be used to certify or quantify findings: doctors may use electroencephalogram (EEG) tests to monitor the electrical activity in the brain, blood tests to check for seizure triggers or genetic disorders, or brain imaging technology such as CT scans or MRI scans. These brain imaging exams may reveal unknown tumors or issues in the brain's tissue.

Treatment & Therapy

Grand mal seizures can often be single-occurrence events, so many medical professionals will not begin a treatment regime until another seizure occurs. In that case, they will typically prescribe anti-seizure medication such as carbamazepine, topiramate, pregabalin, or lorazepam. Although typically prescribed one low dosage of a single medication to begin with, most patients require a carefully considered combination of meds in order to reduce their incidence of seizures.

Unfortunately, these treatments may have a variety of negative side effects, and patients should be careful to always take the proper dosage and leave time in between applications. People who are pregnant or are on birth control pills must be especially vigilant – birth defects have been found to be related to certain medications, and some medicines reduce the effectiveness of birth control. Doctors may recommend alternative medications in these cases, such as herbal or traditional remedies. 

Prevention & Prophylaxis

Little can be done to prevent seizures, or to diminish their impact when they do occur. People who are aware that they have seizure disorders should be honest with those around them and instruct them in proper seizure procedure. They should also always wear a seizure armband, bracelet or ankle band so that hospital workers immediately are made aware of any emergency contacts, medication allergies, or current dosages. 

Seizures can be caused by overexposure to bright, flashing lights, and they can be exacerbated by unhealthy behaviors such as overeating and insomnia. People with anxiety or clinical depression should seek treatment for those issues in order to prevent the occurrence of seizures because of them. Seizure-proofing one's home by installing carpets, putting in safety gates, and purchasing safe space heating or kitchen technology can help save the life of a person prone to grand mal seizures.