epilepsy management by dr anoop.k.r
TRANSCRIPT
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Dr Anoop.K.RAsst professor,Dept of general medicine
MMCH
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The following should be considered in the diff. dg. of epilepsy: Syncope attacks (when pt. is standing; results from global
reduction of cerebral blood flow; prodromal pallor, nausea, sweating; jerks!)
Cardiac arrythmias (e.g. Adams-Stokes attacks). Prolonged arrest of cardiac rate will progressively lead to loss of consciousness – jerks!
Migraine (the slow evolution of focal hemisensory or hemimotor symptomas in complicated migraine contrasts with more rapid “spread“ of such manifestation in SPS. Basilar migraine may lead to loss of consciousness!
Hypoglycemia – seizures or intermittent behavioral disturbances may occur.
Narcolepsy – inappropriate sudden sleep episodes Panic attacks PSEUDOSEIZURES – psychosomatic and personality disorders
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The concern of the clinician is that epilepsy may be symptomatic of a treatable cerebral lesion.
Routine investigation: Haematology, biochemistry (electrolytes, urea and calcium), chest X-ray, electroencephalogram (EEG).Neuroimaging (CT/MRI) should be performed in all persons aged 25 or more presenting with first seizure and in those pts. with focal epilepsy irrespective of age.
Specialised neurophysiological investigations: Sleep deprived EEG, video-EEG monitoring.
Advanced investigations (in pts. with intractable focal epilepsy where surgery is considered): Neuropsychology, Semiinvasive or invasive EEG recordings, MR Spectroscopy, Positron emission tomography (PET) and ictal Single photon emission computed tomography (SPECT)
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The majority of pts respond to drug therapy (anticonvulsants). In intractable cases surgery may be necessary. The treatment target is seizure-freedom and improvement in quality of life!
The commonest drugs used in clinical practice are: Carbamazepine, Sodium valproate, Lamotrigine (first line drugs) Levetiracetam, Topiramate, Pregabaline (second line drugs) Zonisamide, Eslicarbazepine, Retigabine (new AEDs)
Basic rules for drug treatment: Drug treatment should be simple, preferably using one anticonvulsant (monotherapy). “Start low, increase slow“. Add-on therapy is necessary in some patients…
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Increase inhibitory neurotransmitter system—GABA
Decrease excitatory neurotransmitter system—glutamate
Block voltage-gated inward positive currents—Na+ or Ca++
Increase outward positive current—K+
Many AEDs pleiotropic—act via multiple mechanisms
dr shabeel
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The brain’s major excitatory neurotransmitter Two groups of glutamate receptors
Ionotropic—fast synaptic transmission NMDA, AMPA, kainate Gated Ca++ and Gated Na+ channels
Metabotropic—slow synaptic transmission Quisqualate Regulation of second messengers (cAMP and
Inositol) Modulation of synaptic activity
Modulation of glutamate receptors Glycine, polyamine sites, Zinc, redox site
dr shabeel
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NMDA receptor sites as targets Ketamine, phencyclidine, dizocilpine block
channel and have anticonvulsant properties but also dissociative and/or hallucinogenic properties; open channel blockers.
Felbamate antagonizes strychnine-insensitive glycine site on NMDA complex
AMPA receptor sites as targets Topiramate antagonizes AMPA site
dr shabeel
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Major inhibitory neurotransmitter in the CNS
Two types of receptors GABAA—post-synaptic, specific
recognition sites, linked to CI- channel
GABAB —presynaptic autoreceptors, mediated by K+ currents
dr shabeel
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Benzodiazepines (diazapam, clonazapam) Increase frequency of GABA-mediated
chloride channel openings Barbiturates (phenobarbital,
primidone) Prolong GABA-mediated chloride channel
openings Some blockade of voltage-dependent
sodium channels
dr shabeel
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Gabapentin May modulate amino acid transport into
brain May interfere with GABA re-uptake
Tiagabine Interferes with GABA re-uptake
Vigabatrin (not currently available in US) elevates GABA levels by irreversibly
inhibiting its main catabolic enzyme, GABA-transaminase
dr shabeel
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Neurons fire at high frequencies during seizures
Action potential generation is dependent on Na+ channels
Use-dependent or time-dependent Na+ channel blockers reduce high frequency firing without affecting physiological firing
dr shabeel
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Phenytoin, Carbamazepine Block voltage-dependent sodium channels at
high firing frequencies—use dependentOxcarbazepine
Blocks voltage-dependent sodium channels at high firing frequencies
Also effects K+ channelsZonisamide
Blocks voltage-dependent sodium channels and T-type calcium channels
dr shabeel
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Absence seizures are caused by oscillations between thalamus and cortex that are generated in thalamus by T-type (transient) Ca2+ currents
Ethosuximide is a specific blocker of T-type currents and is highly effective in treating absence seizures
dr shabeel
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K+ channels have important inhibitory control over neuronal firing in CNS—repolarize membrane to end action potentials
K+ channel agonists would decrease hyperexcitability in brain
So far, the only AED with known actions on K+ channels is valproate
Retiagabine is a novel AED in clinical trials that acts on a specific type of voltage-dependent K+ channel
dr shabeel
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Felbamate Blocks voltage-dependent sodium channels at
high firing frequencies May modulate NMDA receptor via strychnine-
insensitive glycine receptor
Lamotrigine Blocks voltage-dependent sodium channels at
high firing frequencies May interfere with pathologic glutamate
release Inhibit Ca++ channels?
dr shabeel
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Topiramate Blocks voltage-dependent sodium channels at
high firing frequencies Increases frequency at which GABA opens Cl-
channels (different site than benzodiazepines) Antagonizes glutamate action at AMPA/kainate
receptor subtype?Valproate
May enhance GABA transmission in specific circuits
Blocks voltage-dependent sodium channels May also augment K+ channels T-type Ca2+ currents?
dr shabeel
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The enzymes most involved with drug metabolism
Enzymes have broad substrate specificity, and individual drugs may be substrates for several enzymes
The principle enzymes involved with AED metabolism include CYP2C9, CYP2C19, CYP3A
dr shabeel
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Inducers: Increase clearance and decrease steady-state concentrations of other drugs
Inhibitors: Decrease clearance and increase steady-state concentrations of other drugs
dr shabeel
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Inducers Inhibitorsphenobarbital valproateprimidone topiramate (CYP2C19)phenytoin oxcarbazepine (CYP2C19)carbamazepine felbamate (CYP2C19)
dr shabeel
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The enzymes most involved with drug metabolism
Nomenclature based upon homology of amino acid sequences
Enzymes have broad substrate specificity, and individual drugs may be substrates for several enzymes
The principle enzymes involved with AED metabolism include CYP2C9, CYP2C19, CYP3A4
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Inducers Inhibitorsphenobarbital erythromycinprimidone nifedipine/verapamilphenytoin trimethoprim/sulfacarbamazepine propoxyphenetobacco/cigarettes cimetidine
valproate
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Category CYP3A4 CYP2C9 CYP2C19 UGT
Inhibitor ErythromycinClarithromycinDiltiazemFluconazoleItraconazoleKetoconazoleCimetidinepropoxypheneGrapefruitjuice
VPAFluconazolemetronidazoleSertralineParoxetineTrimethoprim/sulfa
TiclopidineFelbamateOXC/MHDOmeprazole
VPA
Inducer CBZPHTPBfelbamateRifampinTPMOXC/MHD
CBZPHTPBRifampin
CBZPHTPBrifampin
CBZPHTPBOXC/MHDLTG (?)
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Phenytoin CYP2C9 CYP2C19 Inhibitors: valproate, ticlopidine,
fluoxetine, topiramate, fluconazole
Carbamazepine CYP3A4 CYP2C8 CYP1A2 Inhibitors: ketoconazole, fluconazole,
erythromycin, diltiazem
Lamotrigine UGT 1A4 Inhibitor: valproate
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Valproate UDP glucuronosyltransferase (UGT)
plasma concentrations of Lamotrigine, Lorazepam CYP2C19
plasma concentrations of Phenytoin, Phenobarbital Topiramate & Oxcarbazepine
CYP2C19 plasma concentrations of Phenytoin
Felbamate CYP2C19
plasma concentrations of Phenytoin, Phenobarbital
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Although many AEDs can cause pharmacokinetic interactions, several newer agents appear to be less problematic.
AEDs that do not appear to be either inducers or inhibitors of the CYP system include:
GabapentinLamotrigineTiagabineLevetiracetamZonisamide
dr shabeel
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First line drug for partial seizures Inhibits Na+ channels—use dependent Prodrug fosphenytoin for IM or IV administration.
Highly bound to plasma proteins. Half-life: 22-36 hours Adverse effects: CNS sedation (drowsiness,
ataxia, confusion, insomnia, nystagmus, etc.), gum hyperplasia, hirsutism
Interactions: carbamazapine, phenobarbital will decrease plasma levels; alcohol, diazapam, methylphenidate will increase. Valproate can displace from plasma proteins. Stimulates cytochrome P-450, so can increase metabolism of some drugs.
dr shabeel
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First line drug for partial seizures Inhibits Na+ channels—use dependent Half-life: 6-12 hours Adverse effects: CNS sedation. Agranulocytosis and
aplastic anemia in elderly patients, rare but very serious adverse. A mild, transient leukopenia (decrease in white cell count) occurs in about 10% of patients, but usually disappears in first 4 months of treatment. Can exacerbate some generalized seizures.
Drug interactions: Stimulates the metabolism of other drugs by inducing microsomal enzymes, stimulates its own metabolism. This may require an increase in dose of this and other drugs patient is taking.
dr shabeel
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Partial seizures, effective in neonates Second-line drug in adults due to more severe CNS
sedation Allosteric modulator of GABAA receptor (increase
open time) Absorption: rapid Half-life: 53-118 hours (long) Adverse effects: CNS sedation but may produce
excitement in some patients. Skin rashes if allergic. Tolerance and physical dependence possible.
Interactions: severe CNS depression when combined with alcohol or benzodiazapines. Stimulates cytochrome P-450
dr shabeel
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Partial seizures Mechanims—see phenobarbital Absorption: Individual variability in rates. Not highly
bound to plasma proteins. Metabolism: Converted to phenobarbital and
phenylethyl malonamide, 40% excreted unchanged. Half-life: variable, 5-15 hours. PB ~100, PEMA 16
hours Adverse effects: CNS sedative Drug interactions: enhances CNS depressants, drug
metabolism, phenytoin increases conversion to PB
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Status epilepticus (IV) Allosteric modulator of GABAA receptors—
increases frequency Absorption: Rapid onset. Diazapam—rectal
formulation for treatment of SE Half-life: 20-40 hours (long) Adverse effects: CNS sedative, tolerance,
dependence. Paradoxical hyperexcitability in children
Drug interactions: can enhance the action of other CNS depressants
dr shabeel
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Partial seizures, first-line drug for generalized seizures. Enhances GABA transmission, blocks Na+ channels,
activates K+ channels Absorption: 90% bound to plasma proteins Half-life: 6-16 hours Adverse effects: CNS depressant (esp. w/ phenobarbital),
anorexia, nausea, vomiting, hair loss, weight gain, elevation of liver enzymes. Hepatoxicity is rare but severe, greatest risk <2 YO. May cause birth defects.
Drug interactions: May potentiate CNS depressants, displaces phenytoin from plasma proteins, inhibits metabolism of phenobarbital, phenytoin, carbamazepine (P450 inhibitor).
dr shabeel
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Absence seizures Blocks T-type Ca++ currents in thalamus Half-life: long—40 hours Adverse effects: gastric distress—pain,
nausea, vomiting. Less CNS effects that other AEDs, transient fatigue, dizziness, headache
Drug interactions: administration with valproate results in inhibition of its metabolism
dr shabeel
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dr shabeel
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Newer Antiepileptic drugsDrugs Mechanism of
actionFDA approved indication
Lamotrigine Inhibits voltage sensitive sodium channels Inhibits synaptic release of glutamate
as adjunctive therapy of partial seizures in patients greater than or equal to 2 years of age and Primary GTC in patients ≥ 13 years of age
Levetiracetam
Binds to synaptic vesicle protein SV2A and impedes nerve conduction
Refractory Partial seizuresRefractory JME
Gabapentin Binds to α2δ subunit of voltage gated calcium channels
Partial seizure with or without secondary generalization
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Drugs Mechanism of action
FDA approved indication
Lacosamide Sodium channel modulation
Add-on for partial epilepsy
Rufinamide Sodium channel modulation
Lennox-Gastaut syndrome in children 4 years and older and adultsAtonic seizures
Zonisamide Inhibition of sodium channels & T type of calcium channel currentsDecreases GABA uptake & increases glutamate uptake
Focal seizure
Vigabatrin Irreversible inhibitor of GABA transaminase
Infantile spasmsAs an adjunctive for refractory partial epilepsy
Newer Antiepileptic drugs
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Approved for add-on therapy, monotherapy in partial seizures that are refractory to other AEDs
Activity-dependent blockade of Na+ channels, may also augment K+ channels
Half-life: 1-2 hours, but converted to 10-hydroxycarbazepine 8-12 hours
Adverse effects: similar to carbamazepine (CNS sedative) but may be less toxic.
Drug interactions: less induction of liver enzymes, but can stimulate CYP3A and inhibit CYP2C19
dr shabeel
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Add-on therapy for partial seizures, evidence that it is also effective as monotherapy in newly diagnosed epilepsies (partial)
May interfere with GABA uptake Absorption: Non-linear. Saturable (amino acid
transport system), no protein binding. Metabolism: none, eliminated by renal excretion Half-life: 5-9 hours, administered 2-3 times daily Adverse effects: less CNS sedative effects than
classic AEDs Drug interactions: none known
dr shabeel
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Add-on therapy, monotherapy for refractory partial seizures. Also effective in Lennox Gastaut Syndrome and newly diagnosed epilepsy. Effective against generalized seizures.
Use-dependent inhibition of Na+ channels, glutamate release, may inhibit Ca++ channels
Half-life—24 hours Adverse effects: less CNS sedative effects than
classic AEDs, dermatitis potentially life-threatening in 1-2% of pediatric patients.
Drug interactions: levels increased by valproate, decreased by carbamazepine, PB, phenytoin
dr shabeel
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Third-line drug for refractory partial seizures
Frequency-dependent inhibition of Na+ channels, modulation of NMDA receptor
Adverse effects: aplastic anemia and severe hepatitis restricts its use (black box)
Drug interactions: increases plasma phenytoin and valproate, decreases carbamazapine. Stimulates CYP3A and inhibits CYP2C19
dr shabeel
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Add-on therapy for partial seizures Binds to synaptic vesicle protein SV2A,
may regulate neurotransmitter release Half-life: 6-8 hours (short) Adverse effects: CNS depresssion Drug interactions: minimal
dr shabeel
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Add-on therapy for partial seizures Interferes with GABA reuptake Half-life: 5-8 hours (short) Adverse effects: CNS sedative Drug interactions: minimal
dr shabeel
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Add-on therapy for partial and generalized seizures
Blocks Na+ channels and T-type Ca++ channels
Half-life: 1-3 days (long) Adverse effects: CNS sedative Drug interactions: minimal
dr shabeel
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Add-on for refractory partial or generalized seizures. Effective as monotherapy for partial or generalized seizures, Lennox-Gastaut syndrome.
Use-dependent blockade of Na+ channels, increases frequency of GABAA channel openings, may interfere with glutamate binding to AMPA/KA receptor
Half-life: 20-30 hours (long) Adverse effects: CNS sedative Drug interactions: Stimulates CYP3A and inhibits
CYP2C19, can lessen effectiveness of birth control pills
dr shabeel
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Add-on therapy for partial seizures, monotherapy for infantile spasms. (Not available in US).
Blocks GABA metabolism through actions on GABA-transaminase
Half-life: 6-8 hours, but pharmacodynamic activity is prolonged and not well-coordinated with plasma half-life.
Adverse effects: CNS sedative, ophthalmologic abnormalities
Drug interactions: minimal
dr shabeel
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First consideration is efficacy in stopping seizures
Because many AEDs have overlapping, pleiotropic actions, the most appropriate drug can often be chosen to reduce side effects. Newer drugs tend to have less CNS depressant effects.
Potential of long-term side effects, pharmokinetics, and cost are other considerations
dr shabeel
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Current treatmentSeizure type First line
treatmentSecond line treatment
Partial seizures CarbamazepineLamotrigineOxcarbazepineLevetiracetam
TopiramateValproateClobazamZonisamide
Generalized seizuresTonic-clonic Sodium Valproate
CarbamazepineLamotrigineClobazam
Absence EthosuximideSodium valproate
ClobazepamLamotrigine
Atypical absence ClobazepamClobazam
LamotrigineCarbamazepine
Myoclonic Sodium valproateClonazepam
LevitiracetamTopiramate
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With secondary generalization First-line drugs are carbamazepine and
phenytoin (equally effective) Valproate, phenobarbital, and primidone are
also usually effective Without generalization
Phenytoin and carbamazepine may be slightly more effective
Phenytoin and carbamazepine can be used together (but both are enzyme inducers)
dr shabeel
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Adjunctive (add-on) therapy where monotherapy does not completely stop seizures—newer drugs felbamate, gabapentin, lamotrigine, levetiracetam, oxcarbazepine, tiagabine, topiramate, and zonisamide
Lamotrigine, oxcarbazepine, felbamate approved for monotherapy where phenytoin and carbamazepine have failed.
Topirimate can effective against refractory partial seizures.
dr shabeel
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Tonic-clonic, myoclonic, and absence seizures—first line drug is usually valproate
Phenytoin and carbamazepine are effective on tonic-clonic seizures but not other types of generalized seizures
Valproate and ethoxysuximide are equally effective in children with absence seizures, but only valproate protects against the tonic-clonic seizures that sometimes develop. Rare risk of hepatoxicity with valproate—should not be used in children under 2.
dr shabeel
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Clonazepam, phenobarbital, or primidone can be useful against generalized seizures, but may have greater sedative effects than other AEDs
Tolerance develops to clonazepam, so that it may lose its effectiveness after ~6 months
Carbamazepine may exacerbate absence and myoclonic, underscoring the importance of appropriate seizure classification
Lamotrigine, topiramate, and zonisamide are effective against tonic-clonic, absence, and tonic seizures
dr shabeel
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A condition when consciousness does not return between seizures for more than 30 min. This state may be life-threatening with the development of pyrexia, deepening coma and circullatory collapse. Death occurs in 5-10%.
Status epilepticus may occur with frontal lobe lesions (incl. strokes), following head injury, on reducing drug therapy, with alcohol withdrawal, drug intoxication, metabolic disturbances or pregnancy.
Treatment: AEDs intravenously ASAP, event. general anesthesia with propofol or thipentone should be commenced immediately.
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Treatment Diazepam, lorazapam IV (fast, short acting)
Followed by phenytoin, fosphenytoin, or
phenobarbital (longer acting) when control is
established
dr shabeel
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No evidence that any new AED was superior in efficacy to old AEDs Eg. CBZ and VPA in efficacy in well-controlled trials of recent-onset epilepsy.
Although seizure control may have improved in rare epilepsies (Vigabatrin for West-Syndrome , Felbamate for LGS), but , seizure control has not improved dramatically in the last 30 years for common seizures (focal, myoclonic and absence)
Further, one in three patients has drug resistant seizures.
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Recent advances…FDA
approved drugs
New applications of existing
drugs
New formulatio
ns in pipeline
Drugs in pipeline
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Clobazam
• Acts by potentiation of GABAnergic transmission via binding to GABA-A receptor
A benzodiazepine with low tendency to produce sedation Lower incidence of loss of therapeutic effect over time,
rendering it appropriate for long term management
• Oct 2011: FDA approved for Clobazam as adjunctive treatment for seizures associated with Lennox-Gestaut syndrome in adults and children 2 years of age and older in a dose of 5-40 mg/day.
Effectiveness was established in two multi-centre controlled studies.
• Most common adverse effects: sedation, lethargy and fatigue
In Dec 2013, FDA issued warning against serious skin reactions that can result in permanent harm and death and approved label changes
Ng YT, Conry JA, Drummond R, Stolle J, Weinberg MA; OV-1012 Study Investigators. Randomized, phase III study results of Clobazam in Lennox-Gastaut syndrome. Neurology. 2011 Oct 11;77(15):1473-81
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Ezogabine• First neuronal potassium channel opener developed for the
treatment of epilepsy
Acts by enhancement of potassium currents mediated by
KCNQ ion channels, thereby reducing hyper excitability
Also potentiates GABA-A receptors via activation of beta 1 &
beta 2 subtype of GABA receptor
Also, weakly blocks sodium and calcium channels
Nov 2011: FDA approved Ezogabine as an adjunctive treatment in
refractory partial-onset seizures based on RESTORE I & II trials
Owen RT Ezogabine: a novel antiepileptic as adjunctive therapy for partial onset seizures. Drugs Today 2010 Nov;46(11):815-22
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Ezogabine (Retigabine)• Absorption is unaffected by food with an absolute
bioavailability of 50–60%• Peak plasma concentration within 1.5 h and half life is 8 – 11
hours
• Not metabolized by the cytochrome P450 system, so minimal drug interactions seen, as below,
Phenytoin & Carbamazepine decrease Ezogabine concentration
Ezogabine inhibits renal clearance of digoxin Alcohol can increase serum Ezogabine concentrations
Serious adverse effects include urinary retention, neuropsychiatric symptoms and QT-interval lengthening that need careful monitoring
French J A et al. Randomized, double-blind, placebo-controlled trial of ezogabine (retigabine) in partial epilepsy. Neurology.2011 May 3; 76(18): 1555-63
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Oxcarbazepine ER• Acts by blockade of voltage sensitive sodium channels Less potent enzyme inducer than carbamazepine
• Oct 2012: FDA approved a once-daily extended-release formulation as an adjunctive therapy for partial seizures in adults and in children > 6 years
• Dose: 1200 – 2400 OD on empty stomach
• PROSPER study, a multicentre, randomized, double-blind trial in 366 patients with refractory partial epilepsy showed efficacy
• Most common adverse effects include headache, dizziness and diplopia
Rare and Serious adverse effects are hyponatremia and suicidal ideation
French JA, Baroldi P, Brittain ST, Johnson JK; PROSPER Investigators Study Group. Efficacy and safety of extended-release oxcarbazepine (Oxtellar XR™) as adjunctive therapy in patients with refractory partial-onset seizures: a randomized controlled trial. Acta Neurol Scand. 2014 Mar;129(3):143-53
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Eslicarbazepine• Third generation AED
• S-licarbazepine: effective component of carbamazepine
with,
fewer cognitive and psychiatric adverse effects
crosses BBB more effectively
lacks a toxic epoxide
minimal interaction with the cytochrome P450 liver
enzymes
Elger et al. showed less incidence of hyponatremia
compared to oxcarbazepineElinor Ben-Menachem. Eslicarbazepine Acetate: A Well-Kept Secret? Epilepsy Curr. Jan 2010; 10(1): 7–8
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• Acts by blockade of fast acting voltage gated sodium channels
• Nov 2013: US FDA approved as an adjunctive treatment for partial onset seizures
• Based on 3 randomized, double blind, multi-centre trials in 1049 patients with partial onset seizures
• Dose: 400-1200 mg/day ; once daily dosing
• Most adverse effects include headache, nausea, ataxia, tremors
Eslicarbazepine
Gil-Nagel A, Elger C, Ben-Menachem E, Halász P, Lopes-Lima J, Gabbai AA, Nunes T, Falcão A, Almeida L, da-Silva PS. Efficacy and safety of eslicarbazepine acetate as add-on treatment in patients with focal-onset seizures: integrated analysis of pooled data from double-blind phase III clinical studies. Epilepsia. 2013 Jan;54(1):98-107
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Parampanel• First-in-class drug, a highly selective, non competitive AMPA
type glutamate receptor antagonist
• Nov 2012: FDA approved for treatment of refractory partial-onset seizures in patients 12 years and older,
based on 3 clinical trials in 1037 adults and adolescents which showed reduced seizure frequency
Dose: 4 – 12 mg OD
• Boxed warning about the risk for serious neuropsychiatric events
• Common adverse effects include dizziness, fatigue, irritability, anxiety, aggression, etc
Steinhoff BJ, Ben-Menachem E, Ryvlin P, Shorvon S, Kramer L, Satlin A, Squillacote D, Yang H, Zhu J, Laurenza A. Efficacy and safety of adjunctive perampanel for the treatment of refractory partial seizures: a pooled analysis of three phase III studies. Epilepsia. 2013 Aug;54(8):1481-9
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Topiramate –extended release
Blockage of voltage-dependent sodium channels
Augmentation of the activity of the neurotransmitter GABA
Antagonism of the AMPA/ kainate subtype of the glutamate
receptor
• March 2014: US FDA approved
As monotherapy for focal seizure and primary GTC in
patients > 10 years and,
As an adjunctive therapy in patients > 2 years for focal
seizures, primary GTC and seizures associated with
Lennox-Gestaut syndrome.
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Withdrawal should be carried out only if pt is satisfied that a further attack would not ruin employment etc. (e.g. driving licence). It should be performed very carefully and slowly! 20% of pts will suffer a further sz within 2 yrs.
The risk of teratogenicity is well known (~5%), especially with valproates, but withdrawing drug therapy in pregnancy is more risky than continuation. Epileptic females must be aware of this problem and thorough family planning should be recommended. Over 90% of pregnant women with epilepsy will deliver a normal child.
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A proportion of the pts with intractable epilepsy will benefit from surgery.
Epilepsy surgery procedures: Curative (removal of epileptic focus) and palliative (seizure-related risk decrease and improvement of the QOL)
Curative (resective) procedures: Anteromesial temporal resection, selective amygdalohippocampectomy, extensive lesionectomy, cortical resection, hemispherectomy.
Palliative procedures: Corpus callosotomy and Vagal nerve stimulation (VNS).
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THANK YOU