Anti-seizure Drugs Flashcards
types of seizures
- simple partial seizures: preserved consciousness
- complex partial seizures: impaired consciousness; with psychological symptoms
- generalised tonic clonic seizures = grand mal seizures
- absence seizures = petit mal; impaired consciousness
- myoclonic seizures
- status epilepticus: series of seizures without recovery of consciousness between attacks
receptors affected by anti-seizure drugs: phenytoin carbamazepine valproic acid phenobarbital topiramate
phenytoin: Na
carbamazepine: Na, glutamate
valproic acid: Na, Ca, GABA, NMDA
phenobarbital: Na, GABA, glutamate
topiramate: Na, Ca, GABA, glutamate, carbonic anhydrase
tradition anti-seizure drug
anti-convulsant (hydantoin)
blocks voltage-gated Na channels
SE: GINGIVAL HYPERPLASIA, hirsutism, anemias, teratogen (fetal hydantoin syndrome)
POTENT INDUCER OF CYP450 ENZYMES
FOLLOWS ZERO-ORDER KINETICS AT HIGH DOSES
phenytoin = diphenyl-hydantoin
fosyphenytoin, mephenytoin, ethotoin
what comprises fetal hydantoin syndrome?
upturned nose
mild mid-facial hypoplasia
long upper lip with thin vermillion border
lower distal digital hypoplasia
traditional anti-seizure drug anti-convulsant (tricyclic) blocks voltage gated Na channels and decreases glutamate release for TRIGEMINAL NEURALGIA (TIC DOLOREAU) POTENT INDUCER OF CYP450 ENZYMES INHIBITED BY ERYTHROMYCIN
carbamazepine
oxcarbazepine, eslicarbazepine
traditional anti-seizure drug
anti-convulsant (branched chain fatty acid)
for GENERALISED TONIC CLONIC SEIZURES, ACUTE MANIA OF BIPOLAR DISORDER
SE: HEPATOTOXICITY (infants), teratogen (NEURAL TUBE DEFECTS), SPINA BIFIDA
INHIBITOR OF CYP450 ENZYMES
Valproic Acid
sodium valproate
acts on GABA transaminase, which degrades GABA
traditional anti-seizure drug
anti-convulsant (barbiturate)
increases DURATION of CL- channel opening
SE: dependence liability greater than benzodiazepines, ACUTE INTERMITTENT PORPHYRIA
POTENT INDUCER OF CYP450 ENZYMES
PREFERRED ANTI-SEIZURE DRUG IN CHILDREN AND PREGNANT WOMEN
Phenobarbital
Primidone
traditional anti-seizure drug anti-convulsant (cyclic ureide) decreases Ca currents (t-type) in thalamus DOC FOR ABSENCE SEIZURES SE: GI distress
ethosuximide
phensuximide, methsuximide
traditional anti-seizure drug
anti-convulsant (benzodiazepine)
increases FREQUENCY of Cl- channel opening
for STATUS EPILEPTICUS
diazepam
lorazepam, clorazepate
traditional anti-seizure drug
anti-convulsant (benzodiazepine)
increases FREQUENCY of Cl- channel opening
for INFANTILE SPASMS
clonazepam
clobazam
traditional anti-seizure drug
anti-convulsant (GABA derivative)
for NEUROPATHIC PAIN (POST-HERPETIC NEURALGIA), MIGRAINE
gabapentin (enhances GABA)
pregabalin
traditional anti-seizure drug anti-convulsant (phenyltriazine) blocks Na and Ca channels decreases glutamate SE: STEVEN JOHNSON SYNDROME
lamotrigine
traditional anti-seizure drug
anti-convulsant (piracetam)
selectively binds vesicular protein SV2A
SE: PSYCHOSIS (due to decreased dopamine levels, schizophrenia develops)
levetiracetam
traditional anti-seizure drug
anti-convulsant (monosaccharide derivative)
multiple actions on synaptic function (Na, Ca, GABA, AMPA-glutamate, carbonic anhydrase)
for: Lennox-Gestaut Syndrome, West Syndrome
SE: PSYCHOMOTOR SLOWING, MEMORY IMPAIRMENT, WEIGHT LOSS, ACUTE MYOPIA, GLAUCOMA, UROLITHASIS
ANTI-SEIZURE DRUG WITH MOST NUMBER OF MECHANISMS OF ACTION
topiramate
DOC for generalised tonic-clonic seizures
valproic acid
phenytoin
carbamazepine
