top of page

Overview of Seizures

According to the Epilepsy Foundation, epilepsy and seizures affect almost 3 million Americans of all ages, at an estimated annual cost of $15.5 billion in direct and indirect costs. A cure does not exist for seizures or epilepsy, but certain medications can prevent epileptic seizures if taken regularly.

Available prescription treatments, however, feature numerous side effects as well as increased health risks for women and older patients. In some cases, the treatments may also be ineffective. Using medical marijuana for seizures has become a growing area of interest for pharmaceutical groups, which have begun clinical trials on medical cannabis for seizure treatment.

Medical marijuana for epilepsy and seizures has also gained support from the Epilepsy Foundation — as well as acknowledgments from organizations like the American Epilepsy Society — as a potential treatment, following the appropriate research and testing trials.

Understanding seizures, as well as their available treatments, is the first step towards understanding why medical cannabis for seizures is a viable treatment option that offers little to no side effects, giving patients relief and safety from seizures while letting them enjoy their daily life.

Seizures have a wide variety of possible symptoms, depending on what parts of the brain are involved. Many types of seizures cause loss of awareness, twitching or shaking of the body. Symptoms of seizures come on suddenly, over just seconds to a minute, and commonly include:

  • Loss of awareness

  • Mental confusion

  • Speech impairment

  • Hallucinations

  • Loss of muscle control and falling

  • Muscle movement, such as twitching, that might spread up or down an arm or leg

  • Muscle tension/tightening that causes twisting of the body, head, arms or legs.

Seizures are classified into three areas: generalized onset, focal onset and unknown onset. All three categories cause electrical impulses in the brain that result in the physical symptoms of a seizure, as discussed above. To break the classification of seizures down further, generalized onset and focal onset seizures each have their own types of seizures.

The six types of generalized onset seizures include:

  1. Grand-Mal or Generalized Tonic-Clonic: Grand-Mal seizures cause you to lose consciousness and collapse. A loss of consciousness is followed by a “tonic” phase, where your body stiffens for 30 to 60 seconds, before a series of violent, jerking movements for another 30 to 60 seconds. Afterward, the body goes into a deep sleep. Around 25 percent of people with epilepsy suffer from this seizure.

  2. Absence: Absence seizures are brief and last only a few seconds, but occur multiple times a day. They’re often hard to spot, since a blank stare is the only symptom. Patients often notice these seizures when they realize they’re missing time from their day. It’s estimated only five percent of patients have this type of seizure.

  3. Myoclonic: Myoclonic seizures cause sporadic jerking. Sometimes this can feel like an electrical shock.

  4. Clonic: Clonic seizures result in repetitive and rhythmic jerks throughout the body. Those with clonic seizures are often hurt by falling, banging their head or biting their tongue, though they’re most often seen in infants.

  5. Tonic: Tonic seizures, as noted in Grand-Mal seizures, cause your body’s muscles to stiffen.

  6. Atonic: Atonic seizures cause a loss of your arm and leg’s muscle tone, which results in falls that can cause further injury. Less than one percent of those with epilepsy have atonic seizures.


The three types of focal onset seizures include:

Focal Onset Aware: Focal onset aware seizures affect 14 percent of people with epilepsy and are divided into four subcategories by symptoms: motor, autonomic, sensory and psychological. These subcategories are distinguished by their symptoms.

Motor symptoms, for example, cause the body to jerk and stiffen, while sensory symptoms cause odd or unusual sensations relating to the senses, such as strange sounds or weird tastes.

Autonomic symptoms relate to what functions your body automates, such as your bladder and intestines, and can cause you to lose control of your bladder during a seizure. Psychological symptoms involve intense emotions of fear or pleasure as well as deja-vu.


Focal Onset Impaired: Focal onset impaired seizures affect 36 percent of those with epilepsy. During these seizures, you lose awareness and your body does a series of repetitive and coordinated movements, like smacking your lips, chewing or even walking.


Partial: Partial seizures begin as either simple or complex before they transition into a violent Grand-Mal seizure. They’re also, in some cases, treatable through surgery.

Unknown onset seizures are seizures not witnessed or seen by other parties — who are essential to helping identifying seizures — as patients can lose consciousness. Seizures are also called “unknown onset seizures” when the beginning of the seizure isn't known.

Because of the violent nature of some of these seizures — 34 percent of sudden deaths in children result from epilepsy — it’s essential that patients have access to medication that treats their symptoms and prevents or reduces future seizures.

Findings: Effects of Cannabis on Seizures

Many patients suffering from epilepsy, and other seizure disorders have found great relief from medical marijuana, either taken by itself or in conjunction with more traditional medications. Others who suffer from seizures, but can’t tolerate anti-seizure medications have used medical marijuana to successfully control their seizures.

Medical marijuana lacks the side effects found in traditional medicines used to treat epilepsy. Marijuana side effects are typically mild and are classified as "low-risk." Recent open-label and gold-standard studies have provided concrete evidence of medical marijuana’s side effects when used with and without anti-seizure medicine.

Side effects in these studies included:

  • Diarrhea in 17 percent of patients

  • Drowsiness in 21 percent of patients

  • Fatigue in 17 percent of patients

  • Decreased appetite in 16 percent of patients

It’s important to note that medical cannabis and the patient’s current anti-seizure medicine can interact, thereby causing certain side effects. Participants in the study also described medical marijuana’s effects, which went away, as mild or moderate.

Seizures in the study decreased by 54 percent for participants in the open-label study, who ranged from 2 to 26 years of age and didn’t respond previously to traditional anti-seizure medicine. Researchers also found that 89 percent of children participants’ seizures were reduced using medical cannabis.

bottom of page