Glossary

Behind uncontrolled seizures could be a more specific diagnosis

The terms "refractory," "intractable," or "drug-resistant" seizures could be a clue to an underlying condition such as Lennox-Gastaut syndrome (LGS), Dravet syndrome, or tuberous sclerosis complex (TSC).

By identifying seizures early on, your doctor can work with you to develop the right treatment plan. Don't wait to get the conversation started. This quick assessment may help you and your doctor determine if the seizures are a sign of something more.

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Tuberous sclerosis complex (TSC)

TSC is a genetic condition characterized by the development of noncancerous tumors that may cause a range of symptoms, including seizures.

Read more here or click below to begin our 8-question assessment.

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Lennox-Gastaut syndrome (LGS)

LGS is a rare form of epilepsy that usually begins in childhood and is associated with multiple types of seizures.

Read more here or click below to begin our 8-question assessment.

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Dravet syndrome

Dravet syndrome is a rare form of epilepsy that typically begins in the first year of life and continues throughout life. It is marked by frequent, often prolonged seizures in the early phases.

Read more here or click below to begin our 8-question assessment.

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TSC
LGS
DS

DS=Dravet syndrome; LGS=Lennox-Gastaut syndrome;
TSC=tuberous sclerosis complex.

Glossary/Tab/Desktop
Absence/petit mal seizures
  • Previously known as petit mal seizures
  • Causes a short period of “blanking out” or staring into space
  • During the seizure, the person's eyelids may flutter
  • Usually affect only a person’s awareness of what is going on at that time, with immediate recovery
Atonic seizures
  • May be referred to as a “drop attack” or “drop seizure”
  • Person has a sudden loss of muscle tone and goes limp
  • Mild seizures look like a head nod or drop, while severe seizures can cause a person to fall to the ground
  • People with these types of seizures may wear helmets to protect from injuries 
Attention-deficit/hyperactivity disorder (ADHD)
  • Chronic condition characterized by a persistent pattern of inattention (inability to maintain focus), hyperactivity (excessive movement that is inappropriate to the setting), or impulsivity (acting on sudden desires without consideration) that interferes with functioning or development
  • Often first identified in school-aged children
  • Affects both children and adults and is more common among boys than girls
Atypical absence seizures
  • Blank staring, with eye blinking, chewing movements, or lip smacking
  • Could include finger or hand rubbing, or other small hand movements
  • Electroencephalogram (EEG) shows a slow-spike wave pattern (SSW)
  • May begin and end gradually, usually lasting for about 5 to 30 seconds
  • May be difficult to distinguish between this seizure type and typical behavior in those with cognitive impairment 
Behavioral issues
  • Issues with behavior or irritability 
Clonic seizures
  • Associated with repeated, rhythmic jerking movements lasting a few seconds to a minute that cannot be stopped by restraining or repositioning the arms or legs
  • Hemi-clonic seizures (a type of focal seizure) occur when sustained rhythmic jerking rapidly involves one side of the body at seizure onset
  • Most commonly occur in babies
  • Often seen as part of a tonic-clonic seizure and may be difficult to distinguish from a myoclonic seizure; however, the jerking is more regular and sustained during a clonic seizure
  • May also be associated with jerking or clonic movements that follow stiffening of muscles, as in a tonic-clonic seizure, and can last seconds to 1 to 2 minutes
Cognitive impairment
  • Or developmental delays, such as losing interest in toys
Developmental delays
  • Losing interest in toys, speech delays, or other delays identified by a doctor
Dravet syndrome
  • Dravet syndrome is a rare form of epilepsy that typically begins in the first year of life and is marked by frequent, often prolonged seizures in the early phases
Focal aware/simple partial seizures
  • Used to be called simple partial seizures
  • Person is fully alert and able to interact

Experiences can include

  • Involuntary motor movements on one side of the body
  • Intense sensory or emotional episodes, such as déjà vu or feeling unexplained emotions
Focal impaired awareness/complex partial seizures
  • Used to be called complex partial seizures
  • Person loses awareness, may not respond, and may have no memory of the seizure

Experiences vary, but can include

  • Starting with a blank stare, followed by chewing/lip smacking
  • Random activity like picking at the air or clothes, attempting to pick up objects, removing clothing, repeating words or phrases, etc
Generalized tonic-clonic/grand mal seizures
  • Formerly known as “grand mal” seizures. This seizures type is what most people think of when they hear the word “seizure”
  • Person loses consciousness or awareness, muscles extend and become rigid, and then jerk rhythmically on both sides of the body 
Infantile spasms/epileptic spasms
  • Occur within first year of life, usually by 4 to 8 months
  • Typically seen as a sudden stiffening of the body and brief bending forward or backward of the arms, legs, and head (can occur with limbs coming inwards towards chest, but not always)
  • Face may grimace or look surprised
  • Some infants arch their backs as they extend their arms and legs
  • Some infants may experience head drops
  • Frequently occur in clusters upon awakening or going to sleep
  • May look like a startle reflex in infants

According to the Epilepsy Foundation, treating seizures early and appropriately is critical to maximizing developmental potential.

Contact your doctor right away if you think your child is having infantile spasms.

Lennox-Gastaut syndrome (LGS)
  • Lennox-Gastaut syndrome (LGS) is a rare form of epilepsy that usually begins in childhood and is associated with multiple kinds of seizures.
Myoclonic seizures
  • Sudden, brief, shock-like muscle movements or jerks that usually don’t last more than a second or two
  • Person is alert
  • May occur in clusters and may be more pronounced upon wakening 
Refactory epilepsy
  • May also be referred to as "uncontrolled," "intractable," or "drug-resistant" epilepsy
  • Occurs when a person has failed to become (and stay) seizure free with adequate trials of 2 appropriately selected antiseizure medications
Renal problems
  • Problems with the kidneys
Severe aggression
  • Aggression that is extreme or unpredictable
Skin problems
  • Including bumps on skin or white spots
Sleep disturbances
  • Difficulty sleeping or staying asleep
Strange eye movements
  • Such as gazing or staring
Tonic seizures
  • Muscles in the body, arms, or legs suddenly become stiff or tense
  • May happen during sleep or can cause a person to fall if standing
  • Typically lasts for less than 20 seconds at a time 
Tuberous sclerosis complex (TSC)
  • Tuberous sclerosis complex (TSC) is a genetic condition characterized by the development of noncancerous tumors that may cause a range of symptoms, including seizures.