Anticonvulsants

Question 1

what is a seizure?

Answer 1

sudden change in behavior dt abn synchronization and excessive electrical activity in the brain
during, neurons may fire as many times at 500 times a second (much faster than regular rate of 80x’s a sec)

Question 2

definition of epilepsy?

Answer 2

recurrent, unprovoked seizures BUT there are multiple causes for a seizure to occur in individuals who do not have epilepsy

Question 3

ssxs most seizures cause? other ssxs?

Answer 3

LOC, notable facial grimacing, jerking or shaking of body
others may present only w/staring spells, visual disturbances, disruption of smell or taste, some will experience an aura before onset of seizure

Question 4

first aid for seizures?

Answer 4

cushion head
remove any eyewear
loosen tight clothing
turn on side
time seizure with a watch
don't put anything in mouth
look for ID
don't hold down
as seizure ends, offer help

Question 5

environmental factors that can lead to increased likelihood of seizures?

Answer 5

flashing lights
sleep deprivation
EtOH consumption 
stress or anxiety
illness

Question 6

causes of non-epileptic seizures?

Answer 6

SOL in the brain
head trauma
drug SEs, toxicity, withdrawal
fever
meningitis, encephalitis
metabolic/electrolyte abnormalities

Question 7

classifications of seizures?

Answer 7

simple (no change in level of consciousness) or complex (change in level of consciousness)
partial/focal (one part or side of the body is affected) or generalized (entire body is affected)
can be further divided into simple partial, complex partial, generalized absence, generalized tonic, generalized clonic, generalized tonic-clonic, status epilepticus

Question 8

60% of ppl w/epilepsy have what kind of seizure?

Answer 8

focal seizures

Question 9

what will someone experience with a simple partial seizure?

Answer 9

will remain conscious but experience unusual feelings or sensations that can take many forms (fear, joy, anger, sadness out of context; hallucinations involving sight, sound, smell, taste, skin sensation)

Question 10

what will someone experience in a complex partial seizure?

Answer 10

has a change in or loss of consciousness
may display strange, repetitious behaviors such as blinks, twitches, mouth movements, motions such as walking in a circle = automatisms
these seizures usu only last a few seconds

Question 11

what will someone experience in absence seizures?

Answer 11

interruption in consciousness where person experiencing the seizure seems to become vacant and unresponsive for a short period of time
slight muscle twitching may also occur
sometimes referred to as petit mal seizures

Question 12

what do tonic-clonic seizures produce as far as sxs?

Answer 12

stiffening of the body, repeated jerks of arms and/or legs as well as LOC
grand mal seizures
involve initial contraction of muscles (tonic phase) which may involve tongue biting, urinary incontinence and absence of breathing
followed by rhythmic muscle contractions (clonic phase)
“epileptic fit”

Question 13

what is status epilepticus? when is a seizure considered an emergency?

Answer 13

refers to continuous seizure activity w/no recovery btw successive seizures
considered a medical emergency if lasts beyond 5 mins (or 2 mins longer than regular seizure length)

Question 14

main 4 MOAs of antiepileptics?

Answer 14

sodium channel blockade
calcium channel (T-type) blockade
potentiate GABA (inhibitory neurotransmission)
decrease glutamate (excitatory neurotransmission)

Question 15

is it possible to determine who will experience SEs from anticonvulsants or at what does?

Answer 15

NO

Question 16

how do anticonvulsants affect electrical d/cs?

Answer 16

either block initiation of electrical d/c from focal area or prevent the further spread of the abn electrical d/c to adjacent brain areas

Question 17

3 first line anticonvulsants? 3 second line drugs? 3 new antiepileptic meds?

Answer 17

1st line: carbamazepine, sodium valproate, lamotrigine
2nd line: levetiracetam, topiramate, pregabaline
new: zonisamide, eslicarbazepine, retigabine

Question 18

initial drug tx is meant to accomplish what two things? usu based on what?

Answer 18

meant to suppress or reduce the incidence of seizures

determine what type to use based on the seizures the individual is experiencing

Question 19

basic rules for anticonvulsant therapy?

Answer 19

tx should be simple, consisting of monotherapy

“start low, increase slow”

Question 20

6 drugs that are potentially effective against partial seizures?

Answer 20

carbamazepine/tegretol
phenytoin/dilantin
diazepam/valium
primidone/mysoline
valproic acid/depakote
lamotrigine/lamactil

Question 21

3 drugs that are potentially effective against abscene seizures (petit mal)

Answer 21

ethosuximide/zarontin
valproic acid/depakote
clonazepam/klonapin

Question 22

what drug is used to tx epilepsy in children and adults? also approved for tx’ing what?

Answer 22

topiramate
also approved for prevention of migraines, bipolar d/o or to counteract wt gain associated w/numerous antidepressants
can also, also tx tremor, bulimia, OCD, alcoholism, smoking cessation, neuropathic pain, cluster h/a, cocaine dependence, borderline personality d/o

Question 23

4 drugs potentially effective for tx’ing status epilepticus?

Answer 23

diazepam/valium
lrazepam/ativan
midazolam/versed
phenobarbital/phenobarb

Question 24

what do you give to a pt who is having a status epilepticus episode? then what?

Answer 24

give benzodiazepine then restart on anti-seizure drug they have been on or start on phenytoin/dilantin

Question 25

class of phenobarbital/phenobarb? indications? MOA? how to give? onset and half-life? initial drug of choice in what population? metabolism?

Answer 25

class: barbiturate anticonvulsant indication: generalized seizures MOA: enhanced GABA activity give IV/PO relatively slow onset and very long half-life may be initial drug of choice in children w/seizures metabolized by P450 enzymes in liver rarely used since the development of phenytoin/dilantin

Question 26

phenobarbital sodium injection can be used to tx what?

Answer 26

can be used to stop acute convulsions or status epilepticus but benzo such as lorazepam or diazepam usu tried first

Question 27

SEs of phenobarbital/phenobarb? stimulation of what system causes increased metabolism?

Answer 27

SE: CNS depression, drowsiness, assoc w/lower IQ scores in kids undergoing chronic tx stimulation of P450 enzymes can increase metabolism of other drugs and concurrent phenobarb use can lower serum concentration of multiple drugs

Question 28

class of primidone/mysoline? MOA? indications?

Answer 28

class: barbiturate anticonvulsant MOA: exact MOA unknown but pheno is a known metabolite of primidone so GABA mediated inhibition is considered as chief MOA indication: all types of seizure d/os except absence seizures

Question 29

how to give primidone/mysoline? plasma half life? SEs? category?

Answer 29

give PO metabolized in liver 10-12 hrs is plasma half life but half life of metabolites if greater than 48 hrs SEs: nausea, anorexia, H/A, vertigo, ataxia category D (do not use in PG)

Question 30

class of diazepam/valium? MOA? indications?

Answer 30

class: benzodiazepine anticonvulsant MOA: increased sensitivity to GABA receptor sites w/subsequent increased chloride influx which serves to inhibit CNS synaptic transmission indications: grand mal seizures, status epilepticus, seldom if ever used as a chronic tx choice for seizures, anxiety, panic d/o

Question 31

how does diazepam effect GABA levels and glutamate decarboxylase activity?

Answer 31

has NO effect on GABA levels and no effect on glutamate decarboxylase activity but has slight effect on gamma-aminobutyric acid transaminase activity

Question 32

MOA of benzodiazepines?

Answer 32

act via benzodiazepine binding sites as Ca2+ channel blockers and significantly inhibit depolarization-sensitive Ca uptake in rat nerve cell preparations

Question 33

class of clonazepam/klonopin? MOA? indications? how to give? duration of action? SEs?

Answer 33

class: benzodiazepine anticonvulsant MOA: increased sensitivity to GABA receptor sites w/subsequent increased chloride influx which serves to inhibit CNS synaptic transmission indications: alt to ethosuximide or valproic acid for absence seizures, status epilepticus give PO, long acting SEs: drowsiness, altered mentation, additive w/CNS depressants, marked abuse potential, tolerance develops

Question 34

class of phenytoin/dilantin? MOA? indications? how to give? onset? half life? what do you need to monitor?

Answer 34

``` class: anticonvulsant MOA: reduces Na and Ca currents across neuronal membranes indications: prophylaxis for all types of seizures except absence seizures give PO/IV/IM slow onset long half life tolerance can develop need to monitor drug levels, CBC, LFTs ```

Question 35

SEs of phenytoin/dilantin? phenytoin adverse effects?

Answer 35

``` SEs: nystagmus, ataxia, gingival hyperplasia, possible hepatotoxicity, possibly bone marrow suppression, IV admin may cause hypotension and arrhythmias P-450 interactions Hirsutism Enlarged gums Nystagmus Yellow-browning of skin Teratogenicity Osteomalacia Interference w/B12 metabolism (anemia) Neuropathies (vertigo, ataxia, H/A) ```

Question 36

class of carbamazepine/tegretol? MOA? indications?

Answer 36

class: anticonvulsant MOA: reduction of Na and Ca currents across neuronal membranes indications: prophylaxis against all types of seizures except absence seizures, chronic pain such as trigeminal neuralgia, post-herpetic neuralgia, schizophrenia, bipolar d/o

Question 37

how to give carbamazepine/tegretol? SEs? what pt population can not be given carbamazepine/tegretol? what do you need to monitor?

Answer 37

give PO SE: vertigo, N/V, possible bone marrow suppression and aplastic anemia should never be given to pts on monoamine oxidase inhibitors as combo increases risk for all associated SEs and increases risk for hypertensive crisis need to monitor CBCs, LFTs

Question 38

class of valproic acid/depakote? MOA? indications? how to give? seizure effect when combined w/other anticonvulsants?

Answer 38

class: anticonvulsant MOA: unknown, enhancement of GABA transmission has been postulated indications: all seizure types, particularly in absence seizures and combined seizure conditions, bipolar d/o, chronic pn syndromes one of the drugs you can add to monotherapy if one drug doesn't work give PO/IV additive anti-seizure effects when combined w/other anticonvulsants

Question 39

how can valproate tx bipolar d/o instead of lithium?

Answer 39

affects fxn of GABA, by enhancing transmission, making it an alternative to lithium salts in the tx of bipolar d/o

Question 40

MOA of valproic acid/depakote?

Answer 40

blocks the voltage-gated sodium channels and T-type calcium channels --> make it a broad-spectrum anticonvulsant drug

Question 41

SEs of valproic acid/depakote? what vitamin does it effect? effects on PG women and babies?

Answer 41

SE: nausea, insomnia, anxiety, potential for severe hepatotoxicity known to be antagonist of folic acid in PG women irreversible birth defects are 3-10x's higher than average defects such as anencephaly

Question 42

class of ethosuximide/zarontin? indications? MOA? give how? what other anticonvulsant drug does it increase? what line in therapy is it for absence seizures?

Answer 42

class: anticonvulsant indications: absence seizures MOA: unknown, possibly affects T-type Ca ion channels give PO ethosuximide increases phenytoin levels considered first line drug fro treating absence seizures b/c less hepatotoxic than valproic acid

Question 43

SEs of ethosuximide/zarontin?

Answer 43

SE: H/A, N/V, fatigue, ataxia, blurred vision, confusion, skin rashes, insomnia, gingival hyperplasia (mild), notable for possible hepatotoxicity and lupus-like syndrome, intractable hiccoughs

Question 44

class of gabapentin/neurontin? MOA? indications? absorption is decreased by concurrent use with what?

Answer 44

class: anticonvulsant, atypical analgesic MOA: potentiate GABA, affects N-type Ca channels, mimics chemical structure of GABA but doesn't act on brain receptors, halts the formation of new synapses indications: adjunctive tx of partial seizures, chronic pain syndromes such as post-herpetic neuralgia, migraine h/as reduce dose w/renal dysfxn, absorption decreased by concurrent use of antacids

Question 45

SEs of gabapentin/neurontin? special use for withdrawal tx?

Answer 45

SE: somnolence, dizziness, ataxia, H/A, other CNS effects 1200 mg at bedtime taken for 40-60 days has been effective in reducing withdrawal sxs and diminishing desire for methamphetamines and/or cocaine

Question 46

tx for alcohol dependence?

Answer 46

flumazenil (IV), hydroxyzine, gabapentin

Question 47

class of lamotrigine/lamactil? MOA? indications? SEs?

Answer 47

class: anticonvulsant MOA: unknown, may stabilize neurons by decreasing sensitivity to excitatory effects of glutamate and aspartate indications: tonic-clonic (grand mal) seizures, complex partial seizures and seizures resistant to other drug txs give PO SE: dizziness, H/A, rashes, diplopia, somnolence, ataxia

Question 48

first drug approved by FDA for tx'ing type I bipolar d/o?

Answer 48

lamotrigine

Question 49

class of levetiracetam/keppra? MOA? indications? other potential indications?

Answer 49

class: anticonvulsant MOA: unknown, may stabilize neurons by inhibition of calcium movement through presynaptic Ca channels indications: tonic-clonic seizures, complex partial seizures, seizures resistant to other drug txs, neuropathic pain has potential benefits for other psychiatric conditions such as Tourette's, Alzheimer's, autism, bipolar

Question 50

SEs of levetiracetam/keppra?

Answer 50

SE: generally well tolerated by can cause drowsiness, weakness, unsteady gait, coordination problems, H/A, mood changes, nervousness, loss of appetite, vomiting, diarrhea, constipation and rare reports of possible changes in skin pigmentation

Question 51

two meds for partial seizures?

Answer 51

lamotrigine/lamictal | phenytoin/dilantin

Question 52

4 meds for grand mal seizures?

Answer 52

valproic acid/depakote lamotrigine/lamactil levetiracetam/keppra topiramate/topamax

Question 53

med for absence seizures?

Answer 53

ethosuximide/zarontin

Question 54

2 meds for myoclonic seizures?

Answer 54

valproic acid | clonazepam

Question 55

med for febrile seizures?

Answer 55

anti-pyretic such as ibuprofen

Question 56

two drugs for status epilepticus?

Answer 56

diazepam/valium | IV lorazepam/ativan

Question 57

all current drugs, with the exception of what can be used in the tx of complex partial seizures?

Answer 57

ethosuximide

Question 58

4 drugs for generalized/tonic clonic seizures?

Answer 58

valproate/depakote lamotrigine/lamictal levetiracetam/keppra topiramate/topamax

Question 59

drug for absence (petit mal) seizures?

Answer 59

ethosuximide/zarontin

Question 60

for all anticonvulsants what does should you start at? what do you need to monitor? if initial monotherapy doesn't work? tapering? discontinuing?

Answer 60

begin at low dose and titrate to desired effect or until limiting SEs develop follow serum drug levels switch to another drug if not effective at maximum dosing before you try 2 drug therapy always try to taper the dosage never discont abruptly or status epilepticus can be induced

Question 61

other tx options for seizures that aren't meds?

Answer 61

``` ketogenic diet vagus nerve stimulator brain neurostimulators surgery seizure responsive service pet ```

Question 62

3 anticonvulsants that can be used in dual drug therapy?

Answer 62

valproic acid/depakote gabapentin/neurontin levetiracetam/keppra