Anticonvulsants Flashcards
Phenytoin side effects (5)
gingival hyperplasia coarsening of facial features mild neuropathy abn. vit D metabolism risk of SJS
Phenytoin MOA and use
prolongs inactivation of Na+ channels
partial seizures, generalized tonic-clonic seizures
Phenytoin metabolism (2)
metabolized by and induces CYP450s
zero order at therapeutic & high doses, first order at low doses
carbamazepine (Tegretol) MOA (2)
blocks Na+ channels
decreases NE release & reuptake
Carbamazepine (Tegretol) uses (4)
DOC: partial seizures
generalized tonic-clonic
bipolar
trigeminal neuralgia
Carbamazepine (Tegretol) SE (3)
aplastic anemia
agranulocytosis
SJS
DOC: partial seizures
Carabamazepine (Tegretol)
metabolism of carbamazepine is increased by (2)
and decreased by (1)
phenobarbital, phenytoin
valproic acid
carbamazepine increases the metabolism of (5)
phenytoin ethosuxamide valproic acid haloperidol OCPs
Phenobarbital (Luminal) MOA
prolongs opening of Cl- channels at GABA receptor
Phenobarbital (Luminal) use (3)
partial seizures
generalized tonic-clonic seizures
potential for abuse
Lamotrigine (Lamictal) MOA
& something unique about its metabolism
voltage-dependent inactivation of Na+ channels; may also inhibit Ca2+ channels
half-life doubled by valproic acid
Lamotrigine (Lamictal) use & SE (3)
partial seizures
N/V, rash, SJS
Gabapentin (Neurontin) use (2)
adjunct for partial & generalized tonic-clonic seizures, neuropathic pain
taken TID, short half life- pt. compliance issues
Gabapentin MOA
GABA analog, may augment GABA release
Topiramate (Topamax) MOA (3)
blocks Na+ channels
potentiates GABA receptors
inhibits glutamate receptors
may inhibit spread of seizures
topiramate (Topamax) use (3)
partial seizures
tonic-clonic seizures
migraine prevention
topiramate (Topamax) SE (3)
increased metabolism of contraceptives
acute myopia
glaucoma
Valproic acid (Depakene) MOA & uses (2)
blocks Ca2+ channels & Na+ channels
2nd choice for absence seizures
myoclonic seizures
Valproic acid (Depakene) SE (2) and contraindication
GI, hepatotoxicity
pregnancy
Ethosuxamine (Zarontin) MOA & use
inhibits low threshold (T-type) Ca2+ channels
DOC absence seizures
Ethosuxmide (Zarontin) SE (3)
GI irritation
hiccup
metabolism inhibited by vaproate
DOC absence seizures?
Ethosuxamide (Zarontin)
DOC partial seizures?
Carbamazepin (Tegretol)