Epilepsy is a chronic neurological disorder characterized by repeated epileptic seizures resulting from uncontrolled discharges of neurons in the central nervous system. Seizures can be classified as either partial or generalized depending on where in the brain they originate. Common causes of epilepsy include genetic predisposition, brain injury, infection, tumors, and metabolic abnormalities. Treatment involves use of anti-epileptic drugs to control seizures in about 70% of patients, while others may require surgery to remove the seizure focus. Diagnosis involves use of EEG, MRI, and tests to check for underlying medical causes and monitor drug levels.
2. ChapterChapter :9:9
EpilepsyEpilepsy
Presented by: Prof.Mirza Anwar BaigPresented by: Prof.Mirza Anwar Baig
Anjuman-I-Islam's Kalsekar Technical CampusAnjuman-I-Islam's Kalsekar Technical Campus
School of Pharmacy,New Pavel,NaviSchool of Pharmacy,New Pavel,Navi
Mumbai,MaharashtraMumbai,Maharashtra
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3. SeizuresSeizures
A seizure is as a sudden, disorderlyA seizure is as a sudden, disorderly
discharge of cerebral neurons.discharge of cerebral neurons.
Seizures involve aSeizures involve a
transienttransient
alteration in brainalteration in brain
function (motor,function (motor,
sensory,sensory,
autonomic, orautonomic, or
psychic clinicalpsychic clinical
manifestations)manifestations) 33
4. DefinitionDefinition
ll AA chronic neurologic disorderchronic neurologic disorder manifestingmanifesting
byby repeated epileptic seizuresrepeated epileptic seizures (attacks or(attacks or
fits) which result fromfits) which result from uncontrolleduncontrolled
discharges of neuronsdischarges of neurons within the centralwithin the central
nervous systemnervous system
ll The clinical manifestationsThe clinical manifestations rangerange fromfrom aa
major motor convulsion to a brief period ofmajor motor convulsion to a brief period of
lack of awareness. The uncontrollable naturelack of awareness. The uncontrollable nature
of the attacks is characteristic of epilepsy.of the attacks is characteristic of epilepsy.
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5. Epidemiology andEpidemiology and
coursecourse
ll 5% of the population suffer a single sz at5% of the population suffer a single sz at
some timesome time
ll 0.5-1% of the population have recurrent sz0.5-1% of the population have recurrent sz
= EPILEPSY= EPILEPSY
ll 70% = well controlled with drugs (prolonged70% = well controlled with drugs (prolonged
remissions)remissions)
ll 30% epilepsy at least partially resistant to30% epilepsy at least partially resistant to
drug treatmentsdrug treatments
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6. Types of SeizuresTypes of Seizures
ûû Seizures can be classified as either partial orSeizures can be classified as either partial or
generalizedgeneralized
ûû The type of seizure as well as the signs andThe type of seizure as well as the signs and
symptoms that accompany the seizure dependsymptoms that accompany the seizure depend
on the part of the brain in which the seizureson the part of the brain in which the seizures
occuroccur
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7. Types of Seizures -Types of Seizures - PartialPartial
ûû Partial Seizures are seizures that begin locallyPartial Seizures are seizures that begin locally
(in one part of the brain)(in one part of the brain)
i.i. Simple Partial seizureSimple Partial seizure (consciousness not(consciousness not
impaired)impaired)
ii.ii. Complex partial seizureComplex partial seizure (consciousness(consciousness
impaired)impaired)
iii.iii. Secondary generalized seizureSecondary generalized seizure (begins(begins
as partial and transitions into aas partial and transitions into a
generalized seizure)generalized seizure)
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8. Types of Seizures - GeneralizedTypes of Seizures - Generalized
ûû Generalized seizures are bilaterallyGeneralized seizures are bilaterally
symmetric; there is no local onset andsymmetric; there is no local onset and
although they involve the entire brain,although they involve the entire brain,
physical control is rarely lost.physical control is rarely lost.
ûû Types of GS include:Types of GS include:
i.i. Absence seizures (Absence seizures (petit mal)petit mal)-- staring,staring,
slight body movement and short periodsslight body movement and short periods
of unawarenessof unawareness
ii.ii. Myoclonic seizures-Myoclonic seizures- sudden jerks of armssudden jerks of arms
and legsand legs
iii.iii. Atonic seizures (Atonic seizures (drop attacks)-drop attacks)- suddenlysuddenly
collapse or fall downcollapse or fall down
iv.iv. Tonic-clonic seizures (Tonic-clonic seizures (grand mal)grand mal)-- mostmost
severe type of seizure; characterized bysevere type of seizure; characterized by
loss of consciousness, body stiffening,loss of consciousness, body stiffening,
shaking and sometimes tongue bitingshaking and sometimes tongue biting
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9. Partial and GeneralizedPartial and Generalized
Partial Seizure with Secondary
Generalization
Primary
Generalized
Seizure
Partial Seizure
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10. Etiology -Etiology - EpilepsyEpilepsy
û Metabolic defects
û Congenital
malformation
û Genetic
predisposition
û Perinatal injury
û Postnatal trauma
û Myoclonic syndromes
û Infection
û Brain tumor
û Vascular disease
û Fever
û Drug and/or alcohol
abuse
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11. PathogenesisPathogenesis
A seizure occurs when aA seizure occurs when a burstburst
of electrical impulses in theof electrical impulses in the
brain escape their normalbrain escape their normal
limits (past threshold).limits (past threshold).
They spread to neighboringThey spread to neighboring
areas and create anareas and create an
uncontrolled storm of corticaluncontrolled storm of cortical
nerve cell electrical activity.nerve cell electrical activity.
The electrical impulses can beThe electrical impulses can be
transmitted to the muscles,transmitted to the muscles,
causing twitches orcausing twitches or
convulsions.convulsions.
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12. PathogenesisPathogenesis
§§ The 19th century neurologist HughlingsThe 19th century neurologist Hughlings
Jackson suggestedJackson suggested ““aa suddensudden excessiveexcessive
disorderlydisorderly discharge of cerebraldischarge of cerebral
neuronsneurons““ as the causation of epilepticas the causation of epileptic
seizures.seizures.
§§ Recent studies in animal models suggest aRecent studies in animal models suggest a
central role for the excitatory neurotransmitercentral role for the excitatory neurotransmiter
glutamateglutamate and inhibitory gamma aminoand inhibitory gamma amino
butyric acid (butyric acid (GABAGABA) (decreased)) (decreased)
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15. DiagnosisDiagnosis
ûû EEGsEEGs can be used to confirm diagnosis andcan be used to confirm diagnosis and
determine type of seizuredetermine type of seizure
ûû AnAn MRIMRI may be ordered if the initialmay be ordered if the initial
medications pt. is on fail to control seizures ormedications pt. is on fail to control seizures or
a CT scan if pt. is an older adulta CT scan if pt. is an older adult
ûû Plasma levels of electrolytesPlasma levels of electrolytes, glucose and, glucose and
calcium levels, renal function tests, livercalcium levels, renal function tests, liver
function tests and even drug screening may befunction tests and even drug screening may be
performedperformed
Diagnostic testsDiagnostic tests include:include:
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16. DiagnosisDiagnosis
ûû If the pt. has already been diagnosed withIf the pt. has already been diagnosed with
epilepsy: anti-epileptic drug (AED) levels mayepilepsy: anti-epileptic drug (AED) levels may
be tested to ensure that the dosage levels arebe tested to ensure that the dosage levels are
accurateaccurate
ûû An ECG can exclude cardiac cause of symptomsAn ECG can exclude cardiac cause of symptoms
or seizure CSF may be tested for infectionor seizure CSF may be tested for infection
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17. TreatmentTreatment
Current treatment methods can control seizuresCurrent treatment methods can control seizures
for approximately 66% of people with epilepsy.for approximately 66% of people with epilepsy.
TreatmentsTreatments includeinclude::
ûû Anti-epileptic drugs are the most common formAnti-epileptic drugs are the most common form
of treatmentof treatment
ûû Brain surgery is performed if seizures originateBrain surgery is performed if seizures originate
in a small, defined area in the temporal or frontalin a small, defined area in the temporal or frontal
lobes, but is not common otherwise due to addedlobes, but is not common otherwise due to added
risk of damaging vital brain functionsrisk of damaging vital brain functions
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18. Diagnosis & TreatmentDiagnosis & Treatment
cont.cont.
ûû Vagus nerve stimulationVagus nerve stimulation-- a vagus nervea vagus nerve
stimulator is implanted into the cheststimulator is implanted into the chest
beneath the collarbone, wraps around thebeneath the collarbone, wraps around the
vagus nerve and stimulates the brain tovagus nerve and stimulates the brain to
inhibit seizuresinhibit seizures
ûû Children (and some adults) who donChildren (and some adults) who don’’tt
respond to medicinal treatment have beenrespond to medicinal treatment have been
prescribedprescribed a high-fat, high-protein and lowa high-fat, high-protein and low
carbohydrate diet to produce ketones,carbohydrate diet to produce ketones,
which allow the body to use fat instead ofwhich allow the body to use fat instead of
glucose for energy. The exact mechanismglucose for energy. The exact mechanism
for why this works is unknown.for why this works is unknown. 1818
19. Epilepsy - TreatmentEpilepsy - Treatment
§§ The majority of pts respond to drug therapyThe majority of pts respond to drug therapy
(anticonvulsants). In intractable cases surgery may be(anticonvulsants). In intractable cases surgery may be
necessary. The treatment target is seizure-freedom andnecessary. The treatment target is seizure-freedom and
improvement in quality of life!improvement in quality of life!
§§ The commonest drugsThe commonest drugs used in clinical practice are:used in clinical practice are:
Carbamazepine, Sodium valproate, LamotrigineCarbamazepine, Sodium valproate, Lamotrigine (first line drugs)(first line drugs)
LevetiracetamLevetiracetam, Topiramate, Pregabaline (second line drugs), Topiramate, Pregabaline (second line drugs)
Zonisamide, Eslicarbazepine, Retigabine (new AEDs)Zonisamide, Eslicarbazepine, Retigabine (new AEDs)
§§ Basic rules for drug treatment: Drug treatment should beBasic rules for drug treatment: Drug treatment should be
simple, preferably using one anticonvulsantsimple, preferably using one anticonvulsant
(monotherapy).(monotherapy). ““Start low, increase slowStart low, increase slow““..
Add-on therapy is necessary in some patientsAdd-on therapy is necessary in some patients……
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20. Witness ResponseWitness Response
When you see someone having a seizure youWhen you see someone having a seizure you
should:should:
ûû Loosen their clothingLoosen their clothing
ûû Move surrounded objects that the seizingMove surrounded objects that the seizing
individual could hurt him/herself onindividual could hurt him/herself on
ûû Stay until seizure ends to make sure the personStay until seizure ends to make sure the person
is okay and can get upis okay and can get up
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