M2.7 Flashcards
A family of different RECURRENT SEIZURE disorders that have in common the sudden, excessive, and disorderly discharge of cerebral neurons
EPILEPSY
- refers to an abnormal, synchronized, electrical depolarization of neurons in the CNS
- may be caused by:
* idiopathic in nature
* CNS infections
* fever
* metabolic defects
* cerebral trauma
SEIZURE
CLASSIFICATION OF SEIZURE
Etiologic classification
Primary - Idiopathic
Secondary - Symptomatic
CLASSIFICATION OF SEIZURE
Seizure Pattern Classification
Partial
General
CATEGORIES OF SEIZURE
affects the HEMISPHERE
Partial (focal) Seizures
CATEGORIES OF SEIZURE
- Partial that BECOMES generalized
- accompanied by LOSS OF CONSCIOUSNESS
Partial with secondary generalization
CATEGORIES OF SEIZURE
- affects BOTH hemispheres
- accompanied by LOSS OF CONSCIOUSNESS
Primarily generalized seizures
CATEGORIES OF SEIZURE
- arise in ONE cerebral hemispheres
- Simple partial seizure
- Complex partial seizure
PARTIAL (FOCAL) SEIZURES
CATEGORIES OF SEIZURE
PARTIAL (FOCAL) SEIZURE:
* NO alteration of consciousness
SIMPLE PARTIAL SEIZURE
CATEGORIES OF SEIZURE
PARTIAL (FOCAL) SEZIURE:
* LOSS of consciousness
* chewing movements (lip smacking)
* diarrhea and urination
COMPLEX PARTIAL SEIZURE
CATEGORIES OF SEIZURE | GENERALIZED SEIZURES
- GRAND MAL EPILEPSY
- full body convulsion
- uncontrolled urination and defacation
- tounge and cheek may be bitten
TONIC-CLONIC SEIZURE
CATEGORIES OF SEIZURE | GENERALIZED SEIZURES
- PETIT MAL epilepsy
- sudden onset and abrupt cessation
- involves a brief, abrupt, and self-limiting loss of consciousness (BLANK STARE)
- rapid eye blinking
ABSENCE SEIZURE
CATEGORIES OF SEIZURE | GENERALIZED SEIZURES
- rhythmic, jerking spasms
MYOCLONIC SEIZURE
CATEGORIES OF SEIZURE | GENERALIZED SEIZURES
- sudden LOSS of ALL MUSCLE TONE
over relaxation of muscle
ATONIC SEIZURE
CATEGORIES OF SEIZURE | GENERALIZED SEIZURES
- develops in YOUNG children (3 months - 5 years)
- accompanied by HIGH fever
- consist of GTC convulsions of short duration
FEBRILE (INFANTILE) SEIZURE
CATEGORIES OF SEIZURE
- reccurent episodes of GENERALIZED TONIC-CLONIC seizure WITHOUT regaining consciousness
- seizure that lasts more than 5 minutes
STATUS EPILEPTICUS
- Epileptic Syndrome and NOT a seizure type
- characterized by MYOCLONIC JERKS of the body with sudden FLEXION or EXTENSION of the body and limbs
INFANTILE SPASM
ANTISEIZURES OR ANTICONVULSANTS
Glutamate INHIBITOR
Phenytoin
Lamotrigine
Phenobarbital
ANTISEIZURES OR ANTICONVULSANTS
NMDA-receptor antagonist
Felbamate
Valproic acid
ANTISEIZURES OR ANTICONVULSANTS
broadest spectrum
Valproic acid
ANTISEIZURES OR ANTICONVULSANTS
T-type-Calcium channel blocker
Ethosuximide
(Valproic acid)
ANTISEIZURES OR ANTICONVULSANTS
what MOLECULAR TARGET:
Phenytoin, Fosphenytoin, Carbamazepine….
Voltage-gated SODIUM channels
ANTISEIZURES OR ANTICONVULSANTS
what MOLECULAR TARGET:
Ethosuxomide
Voltage-gated CALCIUM channel (T-type)
ANTISEIZURES OR ANTICONVULSANTS
what MOLECULAR TARGET:
Retigabine (ezogabine)
Voltage-gated POTASSIUM channels
ANTISEIZURES OR ANTICONVULSANTS
what MOLECULAR TARGET:
Phenobarbital, Primidone, Benzodiazapines
GABA A receptors
ANTISEIZURES OR ANTICONVULSANTS
what MOLECULAR TARGET:
Tiagabine
GAT-1 GABA transporter
ANTISEIZURES OR ANTICONVULSANTS
what MOLECULAR TARGET:
Vigabatrin
GABA transaminase
ANTISEIZURES OR ANTICONVULSANTS
what MOLECULAR TARGET:
Levetiracetam
SV2A
ANTISEIZURES OR ANTICONVULSANTS
what MOLECULAR TARGET:
Gabapentin, Pregabalinl
α2δ
ANTISEIZURES OR ANTICONVULSANTS
what MOLECULAR TARGET:
Perampanel
AMPA receptor
Calcium channel type for BRAIN
T TYPE
Calcium channel type for HEART
L TYPE
ANTISEIZURES OR ANTICONVULSANTS
prodrug for PHENYTOIN
FOSPHENYTOIN
ANTISEIZURES OR ANTICONVULSANTS
serves largely as a prodrug for LICARBAZEPINE
OXCARBAZEPINE
ANTISEIZURES OR ANTICONVULSANTS
a prodrug for S-LICARBAZEPINE
ESLICARBAZEPINE ACETATE
ANTISEIZURES OR ANTICONVULSANTS
prodrug for GABAPENTIN
GABAPENTIN ENACARBIL
ANTISEIZURES OR ANTICONVULSANTS
- PROTOTYPE antiseizure drug
- enzyme inducer capable of auto induction
- DOC for PARTIAL seizure
- DOC for TRIGEMINAL NERUALGIA – one of the most painful condition
- AE: Ataxia, Diplopia, NEURAL TUBE DEFECT (spina bifida), Steven Johnson Syndrome
CARBAMAZEPINE
ANTISEIZURES OR ANTICONVULSANTS
DOC for PARTIAL seizure
CARBAMAZEPINE
ANTISEIZURES OR ANTICONVULSANTS
DOC for TRIGEMINAL NEURALGIA
CARBAMAZEPINE
ANTISEIZURES OR ANTICONVULSANTS | CARBAMAZEPINE
TERATOGENICITY
Neural tube defect (spina bifida)
ANTISEIZURES OR ANTICONVULSANTS | CARBAMAZEPINE
dose-related AE
Ataxia
Diplopia
ANTISEIZURES OR ANTICONVULSANTS
____ has fewer adverse effects and drug interactions that carbamazepines
OXCARBAMAZEPINE
ANTISEIZURES OR ANTICONVULSANTS
- enzyme inducer
- 1ST LINE for FOCAL seizure
- NEVER give intramuscularly (water insoluble)
PHENYTOIN
ANTISEIZURES OR ANTICONVULSANTS
1ST line for FOCAL seizure
PHENYTOIN
ANTISEIZURES OR ANTICONVULSANTS | PHENYTOIN
ADVERSE EFFECT:
most common
nystagmus
ANTISEIZURES OR ANTICONVULSANTS | PHENYTOIN
ADVERSE EFFECTS:
dose-related
ataxia
diplopia
ANTISEIZURES OR ANTICONVULSANTS | PHENYTOIN
ADVERSE EFFECTS:
cosmetic change
gingival hyperplasia - prominent gum
hirsutism - hair overgrowth
ANTISEIZURES OR ANTICONVULSANTS | PHENYTOIN
ADVERSE EFFECTS:
idiosyncratic
Steven Johnson Syndrome
Blood dyscrasia
ANTISEIZURES OR ANTICONVULSANTS | PHENYTOIN
ADVERSE EFFECTS:
teratogenic
Fetal hydantoin syndrome
Carniofacial abnormalities
ANTISEIZURES OR ANTICONVULSANTS | PHENYTOIN
- water SOLUBLE derivative
- can be given IV or IM
FOSPHENYTOIN
ANTISEIZURES OR ANTICONVULSANTS
- has the BROADEST SPECTRTUM
- MOA: increase GABA, block Na, Ca conductance (inhibit Na Ca channel)
- only anticonvulsant that is enzyme INHIBITOR
VALPROIC ACID
ANTISEIZURES OR ANTICONVULSANTS | VALPROIC ACID
ADVERSE EFFECTS
Hepatotoxic
Neural tube defect (spina bifida)
a developmental birth defect involving the neural tube: INCOMPLETE CLOSURE of the embryonic neural tube results in an incompletely formed spinal cord
SPINA BIFIDA
ANTISEIZURES OR ANTICONVULSANTS
- highly PROTEIN BOUND
- SAFE for pregnant and child
- DOC for FEBRILE seizures
PHENOBARBITAL
ANTISEIZURES OR ANTICONVULSANTS
DOC for FEBRILE seizures
PHENOBARBITAL
ANTISEIZURES OR ANTICONVULSANTS | PHENOBARBITAL
- converted to phenobrbital
- alternative choice for adults who have partial and generalized seizures
- 2 active metabolites are phenobarbital and phenylethylmalonamide (PEMA)
PRIMIDONE
ANTISEIZURES OR ANTICONVULSANTS
2 active metabolites of PRIMIDONE
Phenobarbital
Phenylethylmalonamide (PEMA)
ANTISEIZURES OR ANTICONVULSANTS
- Ca channel (T-type) blocker
- DOC for ABSENCE seziure
- reducre the T-type Ca currents in tahalamic neurons
- AE: GI effects, headache, dizziness, blood dyscrasias
ETHOSUXIMIDE
ANTISEIZURES OR ANTICONVULSANTS
DOC for ABSENCE seizure
ETHOSUXIMIDE
ANTISEIZURES OR ANTICONVULSANTS
- Na channel blocker
- effective as monotherapy for PARTIAL seizures
- also active againsts absence and myoclonic seizures in children
LAMOTRIGINE
ANTISEIZURES OR ANTICONVULSANTS
effective monotherapy for PARTIAL seizures
LAMOTRIGINE
ANTISEIZURES OR ANTICONVULSANTS
- SELECTIVELY bind to synaptic vesicular protein (SV2A) preventing the release of glutamate — does not cause drug interaction
LEVETIRACETAM (KEPPRA)
ANTISEIZURES OR ANTICONVULSANTS
- indicated particularly for PARTIAL seizure
- IRREVERSIBLY inhibits GABA aminotransferase (GABA-T) – the enzyme responsible for the degradation of GABA
- typical toxicities: drowsiness, dizziness, weight gain
- contraindicated to patients with MENTAL ILLNESS
- AE: dizziness, nausea, headache, diplopia
VIGABATRIN
ANTISEIZURES OR ANTICONVULSANTS
- blocks NMDA receptors
- has weak effects on sodium channels and little effect on GABA
- increases PLASMA CONCENTRATION of phenytoin and valproic acid concentration but DECREASES levels of carbamazepine
FELBAMATE
ANTISEIZURES OR ANTICONVULSANTS | FELBAMATE
INCREASES plasma concentration of ____ and ____
phenytoin & valproic acid
ANTISEIZURES OR ANTICONVULSANTS | FELBAMATE
DECREASES levels of ____
carbamazepine
ANTISEIZURES OR ANTICONVULSANTS
- an analog of GABA, but NOT acting on GABA receptor
- antiepileptic effect is poorly understood
- effective as an adjunct against PARTIAL and GTC seizures
- AE: somnolence, dizziness, ataxia, headache, and tremor
GABAPENTIN
ANTISEIZURES OR ANTICONVULSANTS
- MOA is similar to carbamazepine and phenytoin
- also potentiates inhibitory effects og GABA by acting at a different receptor from the BZD or barbiturate site
- AE: cognitive slowing, parathesias, somnolence, fatigue, nervousness, and confusion
TOPIRAMATE
ANTISEIZURES OR ANTICONVULSANTS
- MOA: inhibits GABA uptake
- AE: dizziness, nervousness, tremor, depression, emotional lability
TIGABINE
ANTISEIZURES OR ANTICONVULSANTS
- A sulfonamide derivative effective against PARTIAL and GTC seizures
- MOA is unknown
- AE: drowsiness, cognitive impairment, formation of renal stones
ZONISAMIDE
OTHER DRUGS USED IN THE MNGMT OF EPILEPSY
- potentiates the inhibitory effect of GABA
BENZODIAZEPINES
OTHER DRUGS USED IN THE MNGMT OF EPILEPSY
BENZODIAZEPINES:
most effective in STATUS EPILEPTICUS
OLD DRUG OF CHOICE
DIAZEPAM
OTHER DRUGS USED IN THE MNGMT OF EPILEPSY
BENZODIAZEPINES:
also used in STATUS EPILEPTICUS
NEW DOC
LORAZEPAM
OTHER DRUGS USED IN THE MNGMT OF EPILEPSY
BENZODIAZEPINES:
used in ABSENCE seizure, INFANTILE spasm, MYOCLONIC seizure, and ATONIC seizure
CLONAZEPAM
OTHER DRUGS USED IN THE MNGMT OF EPILEPSY
BENZODIAZEPINES:
adjunt medication in COMPLEX partial seizure
CLORAZEPATE
OTHER DRUGS USED IN THE MNGMT OF EPILEPSY
BENZODIAZEPINES:
used in INFANTILE SPAMS and MYOCLONIC seizures
NITRAZEPAM
OTHER DRUGS USED IN THE MNGMT OF EPILEPSY
- A diuretic (for hypertension) that inhibits CARBONIC ANHYDRASE
- diminish the depolarizing action of bicarbonate ions moving out of neurons via GABA receptor ion channel
- used for ALL TYPES of seizures
ACETAZOLAMIDE
OTHER DRUGS USED IN THE MNGMT OF EPILEPSY
- the FIRST antiepileptic drug
- MOA is unknown
- useful in management of EPILEPSY in patients with PORPHYRIA – specific substance for hemoglobin synthesis
- AE: skin rashes, sedation, behavioral changes
BROMIDE
