Antiepileptic and Antispastic Medication Flashcards
what is epilepsy?
sudden attacks of excessive cortical neuronal discharge interfering w/brain function
what are seizures?
excessive cortical neuronal discharge causing involuntary mvt, disruption of autonomic regulation, illusions, and hallucinations
t/f: epilepsy and seizures are the same thing
false, epilepsy is the disorder, seizures are the event
t/f: pts often can tell when a seizure is coming on
true
what are the causes of epilepsy?
brain damage secondary to tumor, infection, stroke, TBI, CP, neurodegenerative disease, fever
channelopathies
what % of children with CP have seizures?
about 30-50%
febrile seizures are common in ___
children
how long do seizures usually last?
1-2 minutes
why do seizures stop naturally?
bc the brain can’t sustain that level of activity for long
seizures are not necessarily an emergency unless the last >5 minutes
true
what are the types of seizures?
generalized seizures
focal seizures
status epilepticus
what are generalized seizures?
seizures involving the entire cortex in both hemispheres
what type of seizures are tonic-clonic and absence seizures?
generalized seizures
what are tonic clonic seizures?
hypertonicity, stiffening muscles, jerky movement, may have sensation changes leading up to seizure
what are absence seizures?
brief, sudden loss of consciousness, looks like “blanking out” then coming back within a few seconds
are tonic clonic or absence seizures harder to detect?
absence seizures
what is a focal seizure?
affecting a restricted area of the cortex
what is status epilepticus?
a very serious results of seizures
a seizure lasting longer than 5 minutes or multiple seizures w/in 5 minutes w/o the person returning to normal consciousness b/w
EMERGENCY (can lead to death or brain damage and veg state or coma)
status epilepticus can results from ____ or ____ _____ seizures?
generalized, untreated focal
what are the treatment options for epilepsy?
pharmacotherapy
brain surgery
neurostimulation
behavioral adjustments
what is the most common brain surgery for epilepsy?
temporal lobe resection
what is neurostimuation?
excessive excitation is monitored and sends signals
t/f: early and consistent rx is key in helping epilepsy
true
how do epileptic meds work?
suppress excitability of neurons initiating seizures to eliminate them and their frequency
what are behavioral adjustments for epilepsy?
stress management and getting a regular sleep schedule
what are the 4 mechanisms of action for antiepileptic meds?
1) increase inhibitory effects–> increase GABA
2) decrease excitatory effects–> decrease glutamate
3) decrease NA+ entry
4) decrease Ca2+ entry
antiepileptic meds need to ___ inhibition or ____ excitation or both
increase, decrease
what are the older drugs for epilepsy?
valproate, phenytoin, carbamazepine, primidone, ethosuxmide, Clonazepam, phenobarbital
do older or newer drugs for epilepsy have complex pharmaco kinetic profiles, and narrow therapeutic ranges
older
do older or newer drugs for epilepsy have fewer adverse effects and are therefore safer?
newer
what are the new drugs for epilepsy?
gabapentin, iamotrigine, topiramate, tiagabine, levetiracetam, zonisamide, oxcarbazepine, pregabalin, esilcarbazepine, vigabatrin, lacosamide, vufinamide
why do we still use older drugs for epilepsy if the newer drugs are safer?
we know more about the side effects of the older drugs
there are generic options for the older drugs
there is more flexibility in route of administration with the older drugs
what is the route of administration most times for antiepileptic drugs?
PO (by mouth)
describe the pharmacokinetics of antiepileptic drugs?
PO
extensive distribution w/in the body-needs to get to brain to work
narrow therapeutic window (esp older drugs)
drug interactions occur with many agents and may increase the half life
what are the first line drugs for tonic clonic seizures?
valproate (Valproicacia), Lamotrigine
what is the first line drug for absence seizures?
Ethosuximide
what are the first line drugs for focal seizures?
Phenytoin, Oxcarbazepine
what are alternative first line drugs for seizures?
Gabapentin, Pregabalin
what is Valproate (Depalcene, Depacon)?
indications: generalized and focal seizures (used for bipolar and migraines too)
one of the most effective anti-seizure meds we have
mechanism of action: broad spectrum of activity; inc concentrations of GABA in the brain; increase Na+
side effects:
- common-GI distress, weight gain, increased appetite, hair loss
- tremors
what is one of the most effective anti-seizure meds we have?
Valproate (Depaclene, Depacon)
what are the indications for Valproate (Depaclene, Depacon)?
generalized and focal seizures (used for bipolar and migraines too)
what are side effects of Valproate (Depaclene, Depacon)?
GI distress, weight gain, increased appetite, hair loss
tremors at higher doses
what is the mechanism of action of Valproate (Depaclene, Depacon)?
broad spectrum of activity
inc concentrations of GABA in the brain
increase Na+
t/f: Valproate should be avoided in the first trimester of pregnancy bc it has a 1-2% change for causing neural tube defect
true
what is Lamotrigine (Lamictal)?
indications: tonic-clonic seizures, focal seizures (also used for bipolar to reduce the risk of relapse); known to improve depression in pts with epilepsy
mechanism of action: inactivate volatage-gated Na2+ channels
side effects:
- common: dizziness, headache, ataxia, vision problems (diploplia)
- rash-potentially fatal
- tremor at higher doses
- insomnia
what are the indications for Lamotrigine (Lamictal)?
tonic-clonic seizures
focal seizures
used for bipolar to reduce the risk of relapse
known to improve depression symptoms in pts with epilepsy
what is the mechanism of action of Lamotrigine (Lamictal)?
inactivate volatage-gated Na2+ channels
what are the side effects of Lamotrigine (Lamictal)?
common: dizziness, headache, ataxia, vision problems (diploplia)
rash-potentially fatal
tremor at higher doses
insomnia
t/f: Lamotrigine (Lamictal) is known to improve depression symptoms in pts with epilepsy
true
what is Ethosuximide (Zarontin)?
indications: absence seizures
mechanism of action: dec Ca2+ influx in thalamic neurons; depression of motor cortex and elevation of the threshold of the CNS to convulsive stimulation
side effects: GI distress, headache, dizziness, lethargy, fatigue, movement disorder (dyskinesia, bradykinesia)
what are the indications for Athosuximide (Zarontin)?
absence seizures
what are the mechanisms of action of Ethosuximide (Zarontin)?
dec Ca2+ influx in thalamic neurons
depression of motor cortex and elevation of the threshold of the CNS to convulsive stimulation
what are the side effects of Athosuximide (Zarontin)?
GI distress, headache, dizziness, lethargy, fatigue, movement disorder (dyskinesia, bradykinesia)
do antiepileptic meds have generally long or short half lives?
long
the interaction bw Valproate and Lamotrigine leads to a ___ in half life up to ___ hours
increase, 70
what is Phenytoin (Dilantin, Phenytex)?
indications: tonic-clonic and focal seizures
mechanism of action: block Na+ channels, act on the motor cortex and inhibits the spread of seizure activity
side effects: GI irritation, confusion, sedation, double vision, ataxia
what are the indications for Phenytoin (Dilantin, Phenytex)?
tonic-clonic and focal seizures
what are the mechanisms of action of Phenytoin (Dilantin, Phenytex)?
block Na+ channels
act on the motor cortex and inhibits the spread of seizure activity
what are the side effects of Phenytoin (Dilantin, Phenytex)?
GI irritation, confusion, sedation, double vision, ataxia
what is Gabapentin (Neurotitan), Pregabalin (Lyrica)?
indication: focal seizures; neuropathic pain, restless leg syndrome, anxiety disorders
structurally related to GABA-synthetic GABA that works in the brain
mechanism of action: inc GABA concentrations; dec excitatory, and block Ca2+ channels
common side effects: clumsiness/unsteadiness, uncontrolled eye movement (nystagmus), sedation
what are the indications for Gabapentin (Neurotitan), Pregabalin (Lyrica)?
focal seizures
also used for neuropathic pain, restless leg syndrome, anxiety disorders
what are the mechanisms of action of Gabapentin (Neurotitan), Pregabalin (Lyrica)?
inc GABA concentrations
dec excitatory, and block Ca2+ channels
what are the common side effects of Gabapentin (Neurotitan), Pregabalin (Lyrica)?
clumsiness/unsteadiness, uncontrolled eye movement (nystagmus), sedation
what are other drugs used in the management of seizures and epilepsy?
benzos
what are benzos used for?
status epilepticus
are benzos taken long term for epilepsy? why or why not?
no bc of their risk for tolerance, dependence, and addiction
what are the benzo drugs?
Ativan, Valium, Klonopin, Xanax
what are the common side effects when starting antiepileptic meds?
nausea, abdominal pain, dizziness, lethargy, irritability, anxiety, or mood changes
what are side effects that can occur with higher doses of antiepileptic meds?
motor side effects are common
unsteadiness/ataxia, poor concentration, sleepiness, diploplia, vomiting, tremor
what side effects are specific to certain antiepileptic meds?
rash, hepatic toxicity, severe behavior disturbance, worsening of seizures
t/f: many antiepileptic meds are teratogenic
true
what does it mean that a drug is teratogenic?
they can lead to birth defects, CV defects, cognitive delays, or facial abnormalities
what are the PT implications for antiepileptics?
know if a pt has a hx/risk for seizures
monitor efficacy and toxic effects of their meds (note changes in s/s and frequency of seiures)
schedule pt appropriately (more side effects right after taking meds, so may not want to see them at this time)
environmental considerations: stress and anxiety triggers
pt education on sleep hygiene
pt advocacy
what are common epileptic triggers?
stress and anxiety
loud noises, bright/flashing lights
what is spasticity?
velocity dependent hypertonicity
what are spastic disorders?
UMN lesions, CP, ALS, MS, stroke, SCI, TBI
what is the primary goal of muscles relaxants?
to selectively decrease skeletal muscle excitability or the motor neurons leading to spasticity
what are the 2 mechanisms of action for muscle relaxants?
1) increase the effects of GABA in the CNS
2) polysynaptic inhibition in the SC
what are some drugs commonly prescribed for spasticity?
Baclofen
Diazepam
Gabapentin
Dantrolene Sodium
Botulinum toxin (Botox)
what is Baclofen (Gablofen, Lioresal, Kemstro)?
a synthetic GABA that selectively bind to GABAb receptors in the SC to decrease excitation of alpha motor neurons
how is baclofen administered?
orally or intrathecally
does baclofen work better for conditions of the SC or brain?
SC (MS, SCI)
not so much for brain (CP, stroke)
what are intrathecal injections?
catheter and pump deliver drug to subarachnoid space of the SC
when would intrathecal injections of baclofen be used?
with severe spasticity
intrathecal injections decrease spasticity with ___ drug, and ___ side effects
less, fewer
when pts don’t respond to oral baclofen, what is done?
intrathecal injection
t/f: intrathecal baclofen can be programmed or have control
true
what are therapeutic classifications of Diazepam (Valium)?
muscles relaxants, sedative and antiepileptic
what else can diazepam (valium) be used for?
anxiety and minor surgeries due to sedative effects
what is the mechanism of action of Diazepam (Valium)?
inc GABA-mediated inhibition
long term use of Diazepam (Valium) is limited by what?
tolerance and dependence risk
is Dantrolene sodium (Dantrium) a CNS agent?
NO
what does Dantrolene sodium (Dantrium) do?
it inhibits Ca2+ channel opening in skeletal muscles which reduces the effect of muscle contractions and enhances relaxation
what is Dantrolene effective in treating?
severe spasticity, regardless of the pathology
what muscle spasms is Dantrolene not effective in treating?
muscles spasms of a peripheral origin like musculoskeletal injury
t/f: Dantrolene sodium is safe for children under 5
false
what is a consequence of long term use of Dantrolene?
hepatotoxicity
how is Dantrolene sodium administered?
oral or IV
is botulinum toxin a CNS agent?
NO
what does botulinum toxin do?
it a muscle paralytic (neurotoxin) that reduces spastic dominence
where is botulinum toxin injected?
locally at a muscle or muscle group for spasticity or severe spasms
what are the 2 serotypes of botulinum toxin that are effective in humans?
Type A (Botox, Dysport)
Type B (Myobloc)
relaxation/paralysis from botulinum toxin occurs within ____ days and lasts ____ months
3-7, 2-3
what does the reduced spasticity dominance from botulinum toxin result in?
neuromuscular training needs to occur due to possible weakness
increased residual function
improvements in ADLs
bracing may be needed
what are the side effects of botulinum toxin?
local irritation of the injection site, headache, muscle aches
potential for antibody production that would make the Botox ineffective
each set of botulinum toxin injections should limited to ____ muscles/groups of muscles at a time
1-2
why are botulinum toxin injection limited to 1-2 muscles/groups at a time?
bc of their potential to spread through the body and to the heart
early antispasticity meds are___
oral
t/f: rx of focal or regional spasticity w/botulinum toxin injections can be started early
true
later in treatment of spasticity, intervene with botulinum toxin injections where?
in selective key muscles to modify synergistic movement
what are common side effects of antispastic meds?
sedation/drowsiness/lethargy
dizziness
headache
nausea/vomiting
dry mouth
ataxia
depression
tolerance and physical dependence with long term use
t/f: side effects of antispastic meds can be improved by adjusting the dose of meds
true
what are some PT implications for use of antispastic meds?
the meds complement PT interventions by decreasing spasticity so that we can work with them
there can be a drastic change in muscle tone over a relatively short period of time, so be aware of the laxity of tendinous structures that can lead to hypermobility, weakness, suppression of residual fxn, proper body mechanics, and documentation (of meds and pt responses)
reassess equipment and appropriate rehab services
