Epilepsy Flashcards
A sudden, disorganized electrical discharge in one or
more parts of the brain that interrupts normal brain
signals and disrupts the normal balance of inhibitory and
excitatory input
Seizure
Multiple neurons misfire simultaneously and depending on location and severity
seizure
single occurrence only
seizure
_________ seizures may lead to chronic neurologic disorder = epilepsy
Recurrent
A CNS disorder in which nerve cell activity in the brain
becomes disrupted, causing seizures or periods of
unusual behavior, sensations and sometimes loss of
consciousness
Epilepsy
Defined by the occurrence of at least two unprovoked seizures, with or without convulsions (voluntary muscles violently contract and relax causing uncontrolled shaking), separated by at least 24 hours
Epilepsy
Defined by the occurrence of at least _____unprovoked seizures, with or without convulsions (voluntary muscles violently contract and relax causing uncontrolled shaking), separated by at least ________ hours
two; 24
Chronic neurological disorder
epilepsy
characterized by recurrent seizures
epilepsy
seizure are due to ________________ in the electrical functions of the brain
brief disturbances
Epilepsy is contagious (t or f)
F
Clinical manifestation of epilepsy
seizures
Anything that disrupts the normal homeostasis or stability of neurons can trigger __________ and
seizures
hyperexcitability
occurs when a hyperexcitable neuron leads to excessive excitability of the large group of surrounding neurons
Hyperexcitability and Hyper-synchronization
Hyperexcitation occurs due to the inward
current of _______ and _________ions and ________ such as glutamate and aspartate.
Na; Ca; NT
Principal excitatory neurotransmitter
Glutamate
Principal Inhibitory neurotransmitter
GABA
Causes or Triggers
- Infections
- Acquired brain injuries
- High fever
- Lack of sleep
- Electrolyte Imbalance, Hypoglycemia
- Sudden alcohol, smoking or drug withdrawal
- Flashing lights
- Medications
seizures can start in any of the lobes (t or f)
T
Lobes of the brain
- occipital
- parietal
- frontal
- temporal
Behind frontal lobes
parietal lobe
behind the forehead
frontal lobe
back of the head
occipital lobe
either side of the head
temporal lobe
For processing visual information
occipital
For processing sensory information (touch, pain, taste)
parietal
For movement, planning, decision-making, emotion regulation, solve problems, maintain behavior
frontal
For memory, learning, emotions, and auditory information
temporal
Symptoms: visual disturbances (flashing lights, hallucination) temporary blindness, headache and difficulty with spatial orientation
occipital
Symptoms: tingling or numbness, difficulty understanding spatial relationships or distances, dizziness, vertigo, difficulty reading and writing, pain sensations
parietal
Symptoms: jerking movements (typically one side of the body), difficulty speaking or slurred speech, abnormal sensations, out-of-body experience, impaired
awareness, confusion, changes in mood or behavior
Frontal
Symptoms: auras (strange smells, tastes or déjà vu), altered awareness or confusion, automatisms (repetitive
movement), auditory hallucinations, difficulty speaking or understanding speech
temporal
warning sensations experienced before a seizure
auras
Classifying seizures
- The onset or beginning of a seizure
- A person’s level of awareness during seizure
- Whether movements happen during a seizure
types of seizures
- generalized
- focal
- unknown
Affect both sides of the brain or groups of cells on both sides of the brain at the same time
GENERALIZED ONSET SEIZURES
subclassifications of generalized onset seizures
- tonic-clonic (grand mal)
- absence (petit mal)
- atonic epilepsy
- Most dramatic type of generalized seizure
- May start as a focal seizure first, then generalized when spread to other brain areas
Tonic-Clonic (Grand Mal)
muscle stiffening of the entire body
tonic
rhythmic jerking of the limbs and
face
clonic
Tonic-Clonic (Grand Mal) lasts for _________________
seconds to several minutes
patients lose consciousness in grand mal seizures (t or f)
T
period of confusion or drowsiness
post-ictal phase
“daydreaming” or “spacing
out”
Absence (Petit Mal)
”staring spell” - unresponsive while awake
Absence (Petit Mal)
Absence (Petit Mal)
Brief lapses or impaired
consciousness lasting from
_____________
five to ten seconds
Often occurs in children
Absence (Petit Mal)
Absence (Petit Mal) stops on its own after adolescence (t or f)
T
- Patient may stare blankly,
blink rapidly, or appear
fidgety - Usually, no jerking movements or other physical manifestations, lip smacking
Absence (Petit Mal)
non-convulsive seizure
Absence (Petit Mal)
“Akinetic” or “Drop seizures”
Atonic Epilepsy
Sudden loss of muscle tone, strength or control, causing the person to fall
Atonic Epilepsy
- May involve the entire body or just certain muscle groups
- usually lasts for a few second
- Brief loss of consciousness may occur
Atonic Epilepsy
- previously known as partial seizure
- Can start in one area or group of cells in one side of the brain
Focal onset seizures
Types of focal onset based on awareness
- focal onset aware seizures
- focal onset impaired awareness
- Simple partial seizures (previous name)
- Individuals remain fully aware of their surroundings
- May experience unusual sensations, movements, or other changes related to the affected brain area
- No lost of consciousness
Aware Seizures
- Complex partial seizures (previous name)
- Involves a degree of altered awareness or confusion
- Individual may appear dazed, (daydreaming) unresponsive, or engage in automatic behaviors like hand
rubbing, lip smacking or fidgeting without full control or awareness
Impaired Awareness Seizures
- When the beginning of a seizure is not known
- If it’s not witnessed or seen by anyone
- May later be diagnosed as a generalized or focal seizure
Unknown onset seizures
Separates epilepsy simply into groups that involve movement
new classification of seizures
Generalized onset seizures
Motor symptoms (affects muscle movements)
- clonic
- atonic
- tonic
- myoclonus
- epileptic spasms
sustained rhythmic jerking
clonic
sudden loss of muscle tone, strength,
control
atonic
muscle stiffening
tonic
brief and sudden muscle jerking
myoclonus
sudden abnormal repetitive
body flexion
epileptic spasms
Usually called absence seizure (generalized onset seizures)
non-motor symptoms
- Typical or atypical absence seizures
- no involvement of movement; affects other brain function — sensory, autonomic, cognitive, emotional changes
Non-motor symptoms Generalized onset seizures
affects one area of the brain
focal onset
Both sides of the brain are affected
generalized
Symptoms of epilepsy depend on ____________
seizure type
The more areas in the brain affected, the more symptoms can be manifested (t or f)
T
There are no diagnostic laboratory tests for epilepsy (t or f)
T
following GTC seizures, serum
_____________ can be transiently elevated due to the possible release of ________ from the pituitary gland
prolactin levels
Seizures and stress may stimulate the ___________ which regulates hormones by triggering prolactin release
from the pituitary gland
hypothalamus
- very useful in the diagnosis of various seizure disorders
- measure electrical activity of the brain
- cannot definitively diagnose epilepsy or specific seizure type on its own
Electroencephalogram (EEG)
abnormal EEG findings can occur without epilepsy (t or f)
T
- Imaging of temporal lobes
> Structural abnormalities or lesions - not a definitive test for epilepsy
- expensive
Magnetic Resonance Imaging (MRI)
typically not helpful except in the initial evaluation for a brain tumor or cerebral bleeding
Computed Tomography (CT Scan)
- May be performed in the presence of suspected infection
- cerebrospinal fluid for culture test
Lumbar puncture
- Not a first-line diagnostic tool for seizures
- Supportive role in diagnosing seizures when other tests are inconclusive
Positron emission tomography (PET) scan and Single-photon emission computed tomography (SPECT)
Factors favoring successful withdrawal of AEDs
- Seizure-free period of two to four years
- Complete seizure control within one year of onset
- An onset of seizures after age two, but before age 35
- A normal neurologic examination and EEG
most common type of generalized epilepsy occurring in children
Juvenile myoclonic epilepsy
Sudden withdrawal may result to _____________
status epilecticus
a seizure that last longer than 5 mins or has >1 seizure within 5 mins without returning to normal level of consciousness between episodes
status epilepticus
Implanted medical device that is
FDA-approved for use as adjunctive
therapy in reducing the frequency of seizures in adults and adolescents older than 12 years of age with partial-onset seizures that are
refractory to AEDs
Vagus Nerve Stimulation
Placing a spoon in a person’s mouth during a seizure to protect the tongue is RECOMMENDED (t or f)
F
- No AEDs are recommended unless there is presence of risk factors for recurrence
- Avoid alcohol and sleep deprivation
For single unprovoked seizures
Recurrent unprovoked seizures or more than one episode of seizure, sleep-deprived individuals and patients with abnormal EEG results may also benefit with AED therapy
Special situations requiring treatment
Partial seizures (refractory monotherapy)
- Lamotrigine
- Oxcarbazepine
- Topiramate
Partial seizures (newly diagnosed) Adults and Adolescents - First Line Drugs
- Carbamazepine
- Gabapentin
- Oxcarbazepine
- Phenobarbital
- Topiramate
- Valproic Acid
Partial seizures (newly diagnosed) Adults and Adolescents - Alt drugs
- Carbamazepine*
- Lacosamide
- Phenobarbital
- Phenytoin*
- Topiramate*
Partial seizures (Refractory adjunct) - adults
- Gabapentin
- Lamotrigine
- Levetiracetam
- Oxcarbazepine
- Tiagabine
- Topiramate
- Zonisamide
Partial seizures (Refractory adjunct) - children
- Gabapentin
- Lamotrigine
- Oxcarbazepine
- Topiramate
- Cause fewer cognitive impairments
- Memory, language, thinking and judgment skills
Gabapentin and Lamotrigine
- May cause substantial cognitive impairments
- When given in high doses or rapid dose escalation
Topimarate
Most widely used AEDs
`
Carbamazepine, Phenobarbital, Phenytoin, Valproic Acid
Superior to valproic acid for efficacy in the treatment of partial seizures
Carbamazepine
- NEW generation agents
- Received FDA approval for use as monotherapy in
patients with partial seizures
Lamotrigine, Oxcarbazepine, Topiramate
Tonic-Clonic Seizures - traditional treatment
Phenytoin
- increasingly used due to lower incidences of side effects
- With equal efficacy compared to phenytoin
Carbamazepine and Valproic acid
Generally considered the drug of first choice for atonic seizures and for juvenile myoclonic epilepsy (JME)
valproic acid
Alternative agents
Lamotrigine, Topiramate, Zonisamide
FDA-approved as adjunctive treatment of myoclonic
seizures in patients with JME
Levetiracetam
First-line therapy for patients with
- newly diagnosed partial seizures and for patients with
- primary generalized convulsive seizures
Associated with a 1% risk of spina bifida when ingested during
first trimester
carbamazepine
Second-line agent for patients with partial seizures who have
failed initial treatment
useful for chronic pain and other non-epileptic
Beneficial for less severe seizures in the elderly
Gabapentin
Both monotherapy and adjunctive treatment in patients with
partial seizures
Alternative for primary generalized seizure types
Adjunctive therapy for primary GTC seizures
Lamotrigine
Indicated for patients with partial seizures who have failed
initial therapy
Approved for adjunctive treatment of myoclonic seizures in
patients with JME
Adjunctive treatment of primarily generalized seizures in
patients with idiopathic generalized epilepsy
Levetiracetam
Monotherapy
Adjunctive therapy in treatment of partial seizures in adults and children as young as four years of age
first-line drug for patients with primary generalized convulsive seizures
May also be effective in patients not demonstrating a response
to carbamazepine
Oxcarbazepine
Drug of choice for neonatal seizures
- Reserved for patients who have failed therapy with other AEDs
- May be useful given IV in refractory status epilepticus
- Multiple dosage forms available (oral solid, oral liquid, IM,
IV)
- Most inexpensive AED
Phenobarbital
First-line AED for primary generalized convulsive and partial
seizures
Phenytoin
- Second-line agent for patients with partial seizures who have
failed initial treatment - Useful for chronic neuropathic pain and generalized anxiety
disorder
Pregablin
- First-line AED for partial seizures as an adjunct and/or monotherapy
- Approved for the treatment of tonic-clonic seizures in
primary generalized epilepsy
Topiramate
First-line therapy for primary generalized seizures including
myoclonic, atonic, and absence seizures
- Used as both monotherapy and adjunctive therapy for partial
seizures
- Useful in patients with mixed seizure disorders
Valproic acid
Adjunctive treatment of partial seizures
Zonisamide
Neurosensory side effects
- Diplopia
- Blurred visions
- Nystagmus
- Ataxia
- Unsteadiness
- Dizziness
- Headache
Hematologic side effect (leukopenia)
Carbamazepine
Minimal CNS adverse effects and few drug interactions due
to broad therapeutic index
Aggressive behavior in children
Gabapentin
diplopia, drowsiness, ataxia,
headaches
Lamotrigine
sedation, fatigue, and coordination
difficulties
Levetiracetam
dizziness, nausea, headache, diarrhea, vomiting, URTI, constipation, dyspepsia,
ataxia, and nervousness
Oxcarbazepine
- CNS side effects: primary factors limiting the use of phenobarbital
- Hyperactivity in children
- May also cause porphyria and rashes as serious as SJS
Phenobarbital
CNS depressant effects (lethargy, fatigue, incoordination,
blurred vision, higher cortical dysfunction,
and drowsiness)
- Usually transient, can be minimized by slow dosage titration
Phenytoin
Most frequently reported: dizziness, ataxia,
blurred vision and weight gain
Pregablin
- Slow dosage titration and increments
- Main: ataxia, impaired concentration, memory difficulties,
attentional deficits, fatigue, paresthesia, somnolence, and
“thinking abnormally” which rarely has included psychosis - Cognitive dysfunctions in concomitant therapy with
topiramate, valproic acid, or phenobarbital
Topiramate
- Most frequently reported: Gastrointestinal symptoms
(nausea, vomiting, anorexia and weight gain) - Minimize GI complaints: enteric-coated formulation or by
giving the drug with food - Alopecia and hair changes (temporary)
- Most serious side effect: hepatotoxicity
Valproic acid
Most common: somnolence, dizziness, anorexia, headache, nausea, agitation, wordfinding difficulties, irritability
Zonisamide
Drug interaction:
Very significant
Drugs that inhibit CYP3A4 potentially may increase carbamazepine serum
concentrations
Carbamazepine
Drug interaction:
Not likely to occur
- Do not induce or inhibit liver enzymes
Gabapentin
Drug interaction:
- Low potential for pharmacokinetic drug interactions
- Do not induce or inhibit liver enzymes
Lamotrigine
Drug interaction:
- Do not induce or inhibit liver enzymes
- Do not appear to interact with other AEDs, warfarin, digoxin,
or oral contraceptive drugs
Levetiracetam
Drug interaction:
- Decreases the bioavailability of ethinyl estradiol and levonorgestrel
Oxcarbazepine
Drug interaction:
Potent enzyme inducer (increases elimination of any drug
metabolized by CYP450)
Phenobarbital
Drug interaction:
Associated with numerous drug interaction
- Involves altered absorption, metabolism, protein binding
- May enhance or reduce its effects
Dosing
- Must be in mg phenytoin
equivalents or PE
- Example: 75 mg fosphenytoin to 50 mg phenytoin sodium
Phenytoin
Drug interaction:
Unlikely to happen, predominantly
excreted unchanged in the urine and undergoes negligible metabolism
Pregabalin
Drug interaction:
Highly protein-bound, can be displaced by other drugs
Valproic acid
Drug interaction:
- Do not induce or inhibit liver
enzymes - Should be avoided in patients
allergic to sulfa drugs
Zonisamide
