48 - 49 PCOL of seizure disorders Flashcards
lowering the seizure threshold: medications
usual doses
- bupropion
- clozapine
- theophylline
- varenicline
- phenothiazine antipsychotics
- CNS stimulants (amphetamines)
lowering the seizure threshold: medications
high doses and impaired renal function
- carbapenems (imipenem)
- lithium
- meperidine
- penicillin
- quinolones
- tramadol
___ seizures are the most common
partial
Lifelong treatment?
not necessarily - long term studies have shown that successful antiseizure medication withdrawals may occur after a seizure free period of ___ - ___ years
2-5
Lifelong treatment?
risk factors for recurrence
- < 2 years seizure free
- onset of seizure after age ___
- history of atypical febrile seizures
- 2-6 years before good seizure control
- greater than __ seizures before control acheived
- ___ seizures most common
- abnormal EEG throughout treatment
- brain injury, dementia
- withdrawal or ___ or ___
- 12
- 30
- partial
- pheytoin, valproate
drug resistant epilepsy
failure of at least ___ trials of antiseizure meds
reasons for failure
- failure to reach ___ target
- alteration of drug targets in the CNS
- drugs missing the real target
management
- rule out wrong drug/diagnosis (pseudo-resistance)
- ___ therapy
- electrical/surgical intervention
2
CNS
combo
status epilepticus
defined as continuous seizure activity lasting ___ min or more
OR
two or more discrete seizures with incomplete ___ between seizures
- ___ drug therapy commonly used in this situation
possible drug therapy
- ___ (first line) - lorazepam or midazolam
- levetiracetam
- valproate
- lacosamide
- phenobarbital
- pheytoin
- topiramate
5, recovery
- IV
- benzodiazepines
status epilepticus treatment
0-5 min (stabilization
- start ECG and ___ if needed
- check serum concentration of antiseizure meds and electrolytes
- if BG low, treat with D25-D50
5-20 min (initial treatment phase)
- if seizure continues IV ___ or IV ___
- alternatives if hese are nor effective: rectal ___ or intranasal/buccal midazolam
20-40 min (second treatment phase)
- if seizure continues: IV ___ , IV ___ , IV ___
- may use ___ phenobarbitalif there is not access to above meds
40-60 min (third phase)
- repeat second line therapy
- anesthetic doses of the following plus continuous EEG monitoring (thiopental, midazolam, phenobarbital, propofol)
- O2
- midazolam, lorazepam
- diazepam
- fosphenytoin, valproic acid, levetiracetam
- phenobarbital
phenytoin/fosphenytoin loading dose
phenytoin contains ___, leads to hypotension, limits infusion rate
- ___ mg/kg IV, may give additional dose 10 min after load
- up to ___ mg/min IV infusion
propylene glycol
20
50
phenytoin/fosphenytoin loading dose
produrg of phenytoin, better IV tolerance
- ___ mg PE (phenytoin equivalents) / kg IV, may give additional dose 10 min after load
- up to ___ mg PE/min IV infusion
20
150
phenytoin/fosphenytoin loading dose
- cardiac monitoring required
- may also cause a local reaction called ___
purple glove syndrome
oral phenytoin dosing considerations
MUST obtain both phenytoin serum concentration and serum ___ in the same blood draw
- therapeutic serum concentration range: ___ - ___ mcg/mL
phenytoin is highly ___ bound
valproae loading dose
IV to PO conversion __ : ___ mg/mg
- LD:15 - 30 mg/kg IV
- subsequent doses: 15 mg/kg/day titrated to 60 mg/kg/day
desired serum concentration = ___ mcg/mL (range ___ - ___ mcg/mL)
1:1
80, 50-120
first line treatments
partial onset
CLLOPPV
carbamazepine
lamotrigine
levetiracetam
oxcarbazepine
phenytoin
pregabali
valproate
first line treatments
tonic-clonic (generalized)
CLOPPV
carbamazepine
lamotrigine
oxcarbazepine
phenobarbital
phenytoin
valproate
first line treatments
absence (generalized)
ELV
ethosuximide
lamotrigine
valproate
first line treatments
myoclonic (focal or generalized)
LTV
levetiracetam
topiramate
valproate
first line treatments
lennox-gastaut
FLRTV
felbamate
lamotrigine
rufinamide
topiramare
valproate
first line treatments
atonic (generalized)
VLRT
valproate
lamotrigine
rufinamide
topiramate
1A2 and 2C9 inducers, UGHR inducers
CPP
carbamazepine
phenobarbital
phenytoin
3A4 inducers
CLOPPT
carbamazepine
lamotrigine
oxcarbazepine
phenobarbital
phenytoin
topiramate
UGT inhibitor
valproate
lamotrigine dosing
boxed warning for ___
- ___ substrate, high initial serum concentrations associated with boxed warning
SJS/TEN
UGT
lamotrigine dosing
dosing with UGT inhibitor ( ___ )
___ mg every other x14 days
___ mg daily x14 days
___ mg daily x 7 days
___ mg daily
valproate
25
25
50
100
lamotrigine dosing
without concomitant UGT drug interactions
___ mg daily x14 days
___ mg daily x14 days
___ mg daily x 7 days
___ mg daily
25
50
100
200
lamotrigine dosing
with UGT inducers ( 3)
___ mg daily x14 days
___ mg daily x14 days
___ mg daily x 7 days
___ mg daily
carbamazepine, phenytoin, phenobarbital
50
100
200
400
anticonvulsant hypersensitivity syndrome
- black box warning - genetic screen for ___ allele prior to initiating ___ or its derivatives
- pts with positive allele should avoid that drug/derivatives
- strong correlation for this allele and AHS in pts of ___ descent
- positive ___ in those of northern european and asian descent may confer similar risk
- HLA-B*1502, carbamazepine
- asian
- HLA-A*3101
DRESS Syndrome
potentially life threatening - estimated mortality rate of 10%
- occurs ___ - ___ weeks after initiation of drug therapy
- associated with carbamazepine, cenobamate, lamotrigine, phenobarbital, phenytoin, valproate, zonisamide
- increased risk in pts with ___ allele (northern european/asian)
2-6
HLA-A*3101
antiseizure drug withdrawal syndrome
associated with ___ D/C
- may cause recurrence of seizures
- should always be ___ for D/C
abrupt
tapered
antiseizure drug therapt in pregnancy
- drug serum concentrations may be altered due to changes in ___
- many antiseizure medications have known teratogenic risks
- ___ is not recommened in pregnancy due to neural tube defecrs and decreased ___ in the offspring
- supplemental ___ should be considered during pregnancy
- infant should receive vitamin L 1 mg IM at birth ro decrease risk of ___ disease
Vd
valproate, IQ
folic acid
hemorrhagic
contraceptic drug interactions
- mediated by CYP ___ induction - estrogen compunds are major ___ substrates
- antiseizure drugs that are inducers will significantly lower the serum concentration/efficacy of estrogen containing contraceptives
interaction can be minimized by using higher-dose estrogen contraceptives - warning for increased risk of thromboembolism
- can use progestin only contraceptives (depo or IUDs too)
- estrogen can significantly decrease ___ serum concentration (50%) and ___ decreases ___ concentrations
3A4, 3A4
lamotrigine, lamotrigine, estrogen
cardiovascular AE
- lamotrigine, phenytoin/fosphenytoin assocaited with ___
- lacosamide and pregabalin cause ___ interval changes
- heart block: ___
- fenfluramine assocaited with ___ heart disease
arrhythmia
PR
lacosamide
valvular
electrolytes, acidosis, and bone loss
carbamazepine and its derivatives cause hypo ___ and syndrome of inappropriate ___ release
phenytoin - altered vitamin ___ metabolism and decreased ___ concentrations leading to osteoporosis with long term use
topiramate - decreased serum bicarbonate leading to metabolic acidosis, kidney ___, monitor serum bicarb ( is also a ___ inhibitor)
- associated with decreased ___ , heat intolerance, and oligohydrosis
- hyponatremai, ADH (SIADH)
- D, Ca
- stones
- carbonic anhydrase
- sweating
psychiatric SE of antiseizure meds
levetiracetam
- psychosis, suicidal, mood changes, depression (most often seen in children)
perampanel
- boxed warning: ___ events (use in caution with previous existing psychosis)
valproate
- acute mental status changes related to ___ ; differentiate from sedation SE
topiramate
- associated with ___ dsyfunction is dose increased to rapidly, uses a slow dosen titration
psychosis
neuropsychiatric
hyperammonemia
cognitive
vision abnormalities
topiramate
- post marketing warning for vision loss, myopia. and ___ detachement
vigamabtrin
- CI in pts who have other risk factors for irreversible vision loss
rentinal
respiratory depression
evaluate apptopriateness of ___ or pregabalon use and risk for respiraotry depression in pt taking CNS depresseants, pulmonary disease, or elderly
gabapentin
pregabalin
clinical pearls
carbamazepine: strong CYP ___ , ___ , ___ , and ___ and P-GP inducer
oxacarbazepine induced ___
1A2, 2C9, 2C19, 3A4
- 3A4
carbamazepine and its derivatives cause ___
hyponatremia
valproate and cause ___ - monitor CBC/platelets
can cause ___ , weight gain, and sedation
thrombocytopenia
PCOS
topiramate and zonisamide
- weight ___
- oligohydrosis
- kidney ___
loss
stones
phenytoin absorption is ___ when given with ___ feedings. Hold feeding __ - ___ hours before or after
decreased
enteral
1-2
phenytoin causes ___ hyperplasia and ___
gingival
hyperplasia
zonisamide is CI if theres a ___ allergy
sulfa
gabapentin and pregabalin are ___ eliminated, decrease dose in impairment
renally
lamortrigine has been assoicated with ___ in people with inderlying cardiac conditins
arrhythmia
T or F: cannabis and THC can help control seizures, epecially those refractory to current AED medications
T
used for lennox-gastaut and dravet syndrome
epidiolex - ___ oral solution
- indicated for ___ and ___ syndrome
cannabidiol
lennox-gastaut
dravet
keto diet
- most often used in ___ seizure disorders to reduce frequency, can be used in adults with refractory seizures
fats:carbs/proteins ___ : ___ or ___ : ___
SE:
- hyperlipidemia
- weight ___
- constipation
- kidney stones
- decreased bone mass/growth
adults seem to response only while one the diet. Effects in chidlren may continue after diet is D/C
child
3:1, 4:1
loss
depresssion in epilepsy
T or F: all seizure drugs carry a warning for increased risk of sucidal thinking
T
depresssion in epilepsy
antidepressants also carry a warning for increased risk of suicidal thinking in patients < ___ years old
24
depresssion in epilepsy
use of ___ should be avoided in patients with uncontrolled seizure disorders
bupropion
