The AnticonvulsantsThe Anticonvulsants

Seizure ClassificationSeizure Classification

Partial Seizures : FocalPartial Seizures : Focal• Simple Partial SeizureSimple Partial Seizure–Consciousness Not ImpairedConsciousness Not Impaired–Convulsions limited to one limbConvulsions limited to one limb–Sensory hallucinationsSensory hallucinations–Common in older children and adultsCommon in older children and adults

Complex Partial SeizureComplex Partial Seizure• Consciousness is impaired brieflyConsciousness is impaired briefly• Automatisms present : Automatic Automatisms present : Automatic

behaviors like lip smacking, behaviors like lip smacking, chewingchewing• Post seizure confusion : 1-2 Post seizure confusion : 1-2

minutesminutes

Partial Become GeneralizedPartial Become Generalized• Consciousness is impairedConsciousness is impaired

• Progressive seizure involvement Progressive seizure involvement until a generalized tonic-clonic until a generalized tonic-clonic seizure evolvesseizure evolves

Generalized SeizuresGeneralized Seizures• Absence Seizures (Petit Mal)Absence Seizures (Petit Mal)–Sudden, brief LOCSudden, brief LOC

–Amnesia for a brief periodAmnesia for a brief period

–Attacks last <30 secondsAttacks last <30 seconds

–No confused state after seizureNo confused state after seizure

–May occur many times per dayMay occur many times per day

Myoclonic SeizuresMyoclonic Seizures–Sudden, lightening fast contractionsSudden, lightening fast contractions–Loss of consciousness may occurLoss of consciousness may occur–Can last seconds to minutesCan last seconds to minutes

Clonic SeizuresClonic Seizures–Rhythmic, synchronized Rhythmic, synchronized

contractions throughout the contractions throughout the entire bodyentire body

–Loss of consciousnessLoss of consciousness

Tonic SeizuresTonic Seizures–generalized sustained muscle generalized sustained muscle

contractions throughout the contractions throughout the bodybody

–Loss of consciousnessLoss of consciousness

Tonic-Clonic Seizures (Grand Mal)Tonic-Clonic Seizures (Grand Mal)–Major convulsions over the entire Major convulsions over the entire

bodybody

–Contractions occur in an alternating Contractions occur in an alternating tonic and clonic patterntonic and clonic pattern

–May loose bowel & bladder controlMay loose bowel & bladder control

–LOCLOC

–May be preceded by an aura or an May be preceded by an aura or an outcryoutcry

Atonic SeizuresAtonic Seizures–Sudden loss of postural toneSudden loss of postural tone

–Consciousness may be lostConsciousness may be lost

AnticonvulsantsAnticonvulsants…A Plethora Of Drugs…A Plethora Of Drugs

HydantoinsHydantoins BarbituratesBarbiturates IminostilbenesIminostilbenes SuccinimidesSuccinimides BenzodiazepinesBenzodiazepines Valproic AcidsValproic Acids

The HydantoinsThe Hydantoins

Phenytoin (Dilantin)Phenytoin (Dilantin) Mephenytoin (Mesantoin)Mephenytoin (Mesantoin) Ethotoin (Peganon)Ethotoin (Peganon) Phenacemide (Phenurone)Phenacemide (Phenurone)

Phenytoin (Dilantin) - Prototypic Phenytoin (Dilantin) - Prototypic DrugDrug• Made in 1908Made in 1908

• Used for seizure control in 1938Used for seizure control in 1938

• In therapeutic doses, no loss of In therapeutic doses, no loss of consciousnessconsciousness

Dilantin - Mechanism of ActionDilantin - Mechanism of Action

Stabilizes neural membranesStabilizes neural membranes–Interferes w/ sodium ion Interferes w/ sodium ion

movement across the cellmovement across the cell

–May prolong the refractory May prolong the refractory period of excitable cells by period of excitable cells by delaying the influx of potassium delaying the influx of potassium ionsions

Hydantoins -Hydantoins -Adverse Side EffectsAdverse Side Effects

AtaxiaAtaxia HirsuitismHirsuitism HeadacheHeadache DysarthriaDysarthria NystagmusNystagmus Gingival HyperplasiaGingival Hyperplasia

The BarbituratesThe Barbiturates

Phenobarbital (Luminal)Phenobarbital (Luminal) Mephobarbitol (Mebaral)Mephobarbitol (Mebaral) Primidone (Myosline)Primidone (Myosline)

Mechanism Of ActionMechanism Of Action

Phenobarbital - The PrototypePhenobarbital - The Prototype–Anticonvulsant at sub-hypnotic Anticonvulsant at sub-hypnotic

dosesdoses

–Not addictive in therapeutic Not addictive in therapeutic dosesdoses

–Increases threshold for motor Increases threshold for motor cortex stimulationcortex stimulation

–Reduces neurotransmitter Reduces neurotransmitter release thereby quieting the release thereby quieting the brainbrain

–May augment the effects of May augment the effects of GABAGABA

–May inhibit the excitatory effects May inhibit the excitatory effects of glutamateof glutamate

Adverse Side EffectsAdverse Side Effects

AtaxiaAtaxia NystagmusNystagmus Vitamin K deficiencyVitamin K deficiency Folic acid deficiencyFolic acid deficiency Sedation which diminishes over Sedation which diminishes over

timetime

The IminostilbenesThe Iminostilbenes

Carbamazepine (Tegretol)Carbamazepine (Tegretol)

Mechanism of ActionMechanism of Action

Identical action to the Identical action to the HydantoinsHydantoins–Stabilizes the flux of sodium across Stabilizes the flux of sodium across

excitable membranesexcitable membranes

–Inhibits the spread of seizure Inhibits the spread of seizure signalingsignaling

–First used in 1974 in the U.S.First used in 1974 in the U.S.

Adverse Side EffectsAdverse Side Effects DiplopiaDiplopia DrowsinessDrowsiness AtaxiaAtaxia Hematopoeitic SuppressionHematopoeitic Suppression• Aplastic anemiaAplastic anemia• LeukopeniaLeukopenia• ThrombocytopeniaThrombocytopenia

Syndrome of Inappropriate Syndrome of Inappropriate Antidiuretic Hormone Secretion Antidiuretic Hormone Secretion (SIADH)(SIADH)–Water retentionWater retention

–Water intoxicationWater intoxication

–Increased intraocular pressureIncreased intraocular pressure

SuccinimidesSuccinimides

Ethosuximide (Zarontin)Ethosuximide (Zarontin) Methusuximide (Celontin)Methusuximide (Celontin) Phensuximide (Milontin)Phensuximide (Milontin)

Mechanism of ActionMechanism of Action

Suppress nerve signal Suppress nerve signal transmission in the motor cortextransmission in the motor cortex

Increase the threshold for Increase the threshold for stimulationstimulation

Increase glucose transport to the Increase glucose transport to the brain which decreases neuronal brain which decreases neuronal excitabilityexcitability

Adverse Side EffectsAdverse Side Effects

AtaxiaAtaxia DizzinessDizziness EuphoriaEuphoria HeadachesHeadaches

Aplastic AnemiaAplastic Anemia ThrombocytopeniaThrombocytopenia AgranulocytosisAgranulocytosis LeukopeniaLeukopenia Decreased sexual driveDecreased sexual drive

Renal and hepatic toxicityRenal and hepatic toxicity AlopeciaAlopecia HirsuitismHirsuitism Gingival HyperplasiaGingival Hyperplasia

Stevens-Johnson DiseaseStevens-Johnson Disease

Target Lesions On The SkinTarget Lesions On The Skin

–Central dark red zone with Central dark red zone with blistersblisters

–Encompassed by a pallor area Encompassed by a pallor area which is circumscribed by a red which is circumscribed by a red rimrim

–Necrotic vasculitis may be Necrotic vasculitis may be present (capillary damage)present (capillary damage)

–Bloody discharge from these Bloody discharge from these lesionslesions

–May involve the eyes, mouth, May involve the eyes, mouth, lips, tongue, throat, esophagus, lips, tongue, throat, esophagus, gut, bronchopulmonary treegut, bronchopulmonary tree

Cause ????Cause ????

BenzodiazepinesBenzodiazepines

Diazepam (Valium)Diazepam (Valium) Clonazepam (Klonopin)Clonazepam (Klonopin) Clorazapate Dipotassium (Tranxene)Clorazapate Dipotassium (Tranxene)

Mechanism of ActionMechanism of Action

Enhance the effect of GABA - An Enhance the effect of GABA - An inhibitory neurotransmitterinhibitory neurotransmitter

Suppresses the spread of Suppresses the spread of seizure signaling produced by seizure signaling produced by epileptogenic fociepileptogenic foci

Adverse Side EffectsAdverse Side Effects

Vertigo, Ataxia,SyncopeVertigo, Ataxia,Syncope Drowsiness, ConfusionDrowsiness, Confusion Tremor, WeaknessTremor, Weakness

Valproic AcidsValproic Acids

Valproate Sodium (Depakene)Valproate Sodium (Depakene) Divalproex (Depakote)Divalproex (Depakote)

Mechanism of ActionMechanism of Action

Mechanism of action is unknownMechanism of action is unknown–Inhibits GABA TransaminaseInhibits GABA Transaminase

–Inhibits Succinic Semialdehyde Inhibits Succinic Semialdehyde DehydrogenaseDehydrogenase

–Allows GABA to have a longer Allows GABA to have a longer half-lifehalf-life

Anticonvulsants - Medical UsesAnticonvulsants - Medical Uses

Used to control seizuresUsed to control seizures The HydantoinsThe Hydantoins

–Trigeminal neuralgiaTrigeminal neuralgia

–Cardiac arrhythmiasCardiac arrhythmias

TegretolTegretol–Trigeminal neuralgiaTrigeminal neuralgia

–Glossopharyngeal neuralgiaGlossopharyngeal neuralgia

Clinical ConsiderationsClinical Considerations

Is the patient taking their Is the patient taking their medications regularly ????medications regularly ????

Time the rehab session within 30 Time the rehab session within 30 minutes of the last dose to decrease minutes of the last dose to decrease the chances of seizuresthe chances of seizures

Are there any external triggers Are there any external triggers which could set off the which could set off the seizure ??? (light, sound, seizure ??? (light, sound, fatigue, odors)fatigue, odors)

Are the patients changing Are the patients changing medications or changing the medications or changing the dose ???dose ???

Are the patients under unusual Are the patients under unusual stress - divorce, family deaths, stress - divorce, family deaths, etc.etc.

Know the side effects of the Know the side effects of the medicationsmedications

Have a good seizure plan in the Have a good seizure plan in the clinicclinic

Train personnel to appropriately Train personnel to appropriately respond to the seizure eventrespond to the seizure event