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The term EPILEPSY based on Greek

word epilambanein ( meaning to

seize ) was first used by Hippocrates.

He described epilepsy as a disease of the

brain , which should be treated with diet.

Hippocrates provided the firstclassification on epilepsy.

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Seizure: The clinical manifestation of an abnormal and excessive

synchronization of a population of cortical neurons.

Epilepsy: A tendency toward recurrent seizures unprovoked by

any systemic or acute neurologic insults.

Epileptogenesis: sequence of events that converts a normalneuronal network into a hyperexcitable network.

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Epilepsy is a common chronic neurological disorder

characterized by seizures.About 50 million people worldwide have epilepsy, and nearly

two out of every three new cases are discovered in developing

countries.

Is mostly in young children, people over the age of 65 years.

As a consequence of brain surgery, epileptic seizures may

occur in recovering patients.

Epilepsy is usually controlled, but cannot be cured with

medication, although surgery may be considered in difficult

cases. However, over 30% of people with epilepsy do not have

seizure control even with the best available medications

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Epilepsy have number of causes. For example, it is sometimes

caused by brain damage, either through injury or infection, or it may

be caused by stroke, cerebral palsy, tumors, and problems during

birth.

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Genetic influence

Head trauma

Medical disordersDementia

Diseases

Prenatal injury

Developmentaldisorders

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Age Early childhood and after age 65

SexMen are slightly more than women.

Family history

Head injuries

Stroke and other vascular diseases

Brain infections like meningitis.Prolonged seizures in childhood

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A seizure is traceable to an unstable cell

membrane or its surrounding cells. Excess

excitability spreads either locally (focal seizure)

or more widely (generalized seizure).

Normal neuronal activity depends on normal

functioning of excitatory and neurotransmitters;

an adequate supply of glucose, oxygen, sodium,

potassium, chloride, calcium, and amino acids;

normal pH; and normal

receptor function.

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MYCLONIC SEIZURES

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Syncope attacks

Cardiac arrythmias

Migraine

Hypoglycemia

Narcolepsy

Panic attacks

PSEU

DOSE

IZURE

S

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People with epilepsy willoften have abnormalelectrical activityseenon

anelectroencephalograph (EEG).

Variousblood tests and othertestslookingfortemporary and reversible

causesofseizures,mayinclude:

Blood chemistry

Blood sugarCBC (completeblood count)

CSF (cerebrospinalfluid) analysis

Kidneyfunctiontests

Liverfunctiontests

Testsforinfectious diseases

Testsforthe cause and locationoftheproblemmayinclude:

EEG

Head CT or MRI scan

Lumbarpuncture (spinaltap)

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Difficulty learning

Inhaling fluid into the lungs, which can cause aspiration pneumonia

Injury from falls, bumps, or self-inflicted bites during a seizure.

Injury from having a seizure while driving or operating machinery.

Many epilepsy medications cause birth defects -- women wishing to become

pregnant should alert their doctor in advance in order to adjust medications.

Permanent brain damage (stroke or other damage).

Prolonged seizures or numerous seizures without complete recovery between them

Side effects of medications

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Generally,thereisnoknown waytopreventepilepsy

However, properdiet and sleep, and staying away fromillegal drugs

and alcohol, may decrease the likelihood of triggering seizures in people

with epilepsy.

Reduce the riskofhead injuryby wearing helmets during risky

activities; this can help lessen the chance of developing epilepsy.

Persons with uncontrolled seizuresshould not drive.

if you have uncontrolled seizures, you should also avoid activities

wherelossofawareness would causegreat danger, such as climbing to

high places, biking, and swimming alone.

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Treatment

andFirst aid

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Epilepsy is usually treated with medication prescribed

by a physician; primary caregivers, neurologists, and

neurosurgeons all frequently care for people with

epilepsy.

In some cases the implantation of a stimulator of the

vagus nerve, or a special diet can be helpful.

Neurosurgical operations for epilepsy can be palliative,reducing the frequency or severity of seizures; or, in

some patients, an operation can be curative.

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:

Identification / look out for :

Twitching of limbs,

shaking or rigid body.

Abnormal eye movements.

Confusion

Unconsciousness

Unusual breathing pattern.

Clenched jaw

Frothing at the mouth.

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Whatto do??During Seizure

1. If possible try to ease the patient's fall.

2. Try to protect the head3. Try to maintain some privacy for the casualty

After Seizure

1. Remove tight clothing.

2. In unconscious patient use the Recovery Position3. Usually patient recovers on his own in his own time.

4. If time lapsed is more than 10 minutes or if first convulsion, seek

immediate medical help / ambulance.

Do not

1. Feed (liquid or solid) by mouth.

2. Gag the patient or put anything in the mouth.

3. Restrain the patient during the attack.

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Some medications can be taken daily in order to prevent

seizures or reduce the frequency of their occurrence.

These are termed "anticonvulsant" or "antiepileptic" drugs

(sometimes AEDs).

All such drugs have side effects which are idiosyncratic and

others which are dose-dependent; it is not possible to predictwho will suffer from side effects or at what dose the side

effects will appear.

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Sex hormones

Sodium currents/channels

Calcium channels

GABA-A receptors/channels

Glutamate receptors

Carbonic anhydrase inhibition

Synaptic vesicle protein 2A binding

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Main types of seizures and the commondrugs used

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PhenytoinIt is an oldest non-sedative antiepilepsy drug & chemically it is

a diphenyl hydantoin

Mechanism of ActionAt therapeutic levels (10-20 g/ml) blocks the use dependent

Na+ channels inhibits the generation of repetitive action

potentials.

At higher doses it also reduces the influx of

Ca+2 suppresses repetitive firing of neurons &

neurotransmitters

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Pharmacokinetics

Oral absorption is slow

Adverse Effects

Gingival hyperplasiaMegaloblastic anemia

Vitamin K deficiency

Vitamin D Deficiency

Hirutismcongenital malformation

Phenytoin should not be discontinued suddenly it mayprecipitate withdrawal seizures

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Mechanism of Action

It blocks the use-dependent Na+ channels inhibits high

frequency repetitive firing of the neurons in brain

Therapeutic Uses

it is the drug of choice for partial & generalized tonic-clonic seizures

Pharmacokinetic

It is distributed mainly in brain, liver, kidneys

It is metablosied & excreted through urine

Adverse EffectsDrowsiness, dizziness, headache, slurred speech, vertigo,

ataxia, diplopia tolerance develops over a period of few weeks

Teratogenecity

Allergic reactions rashes & fever

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Valproic acid or Sodium Valproate or Valproate semisodium it

is the valproate ion (C3H7)2.CHCOO- which is active form &

absorbed from GIT

Mechanism of Action

Block use dependent Na+ channels

Inhibit GABA transaminase

Activate glutamic acid decarboxylase

At higher concentrations it increase the membrane K+

conductance by activating K+ channels

Therapeutic usesIt is very effective against absence seizures [Basis: Inhibit

Ca+2 influx by blocking T-type Ca+2 channels]

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well absorbed orally

Adverse Effects

` Dose related Weight gain, increase in appetite,GIT distress,

tremors, reversible alopecia

` Causes Hepatotoxicity

` Idiosyncratic reaction

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Clinical Trial Example..

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PURPOSE

This study will evaluate the usefulness of transcranial magnetic stimulation (TMS) in

measuring cortical excitability. The cortex is the outer part of the brain. Patients withseizures have increased cortical excitability and are often treated with antiepileptic

drugs to reduce this excitability.

The therapeutic effects ofantiepileptic drugs are usually tracked with blood tests

that measure their blood levels. However, these blood tests may not always correctly

reflect the effects of the drugs on the brain.TMS has been used successfully to measure cortical excitability in many

neurological diseases, including epilepsy, and may be helpful in

measuring drug effects on the brain directly.

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OBJECTIVES

Transcranial magnetic stimulation (TMS) is a non-invasive technique

that allows accurate measures of this parameter. The purpose of this

protocol is to test the hypothesis that TMS measures of cortical

excitability will correlate with serum blood levels of AEDs, and reflectclinical effects on cortical function directly in healthy volunteers.

This information is crucial to reach the ultimate goal of developing a

reliable quantitative measurement of central physiological effects of

AEDs in epileptic patients.STUDY POPULATION:40 normal volunteers aged 18 to 55 years

will be recruited for this study.

STUDYDESIGN: Subjects will be assigned to either of two groups,

with each group receiving one of the following drugs; carbamazepine

(CBZ), and lamotrigine (LTG).

OUTCOME MEASURES:The primary outcome variables will be

MEP size, measured from recruitment curves. MEP size

difference from baseline will be compared to the

serum drug level for each drug.

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