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Define seizure:
paroxysmal disorder of CNS, characterized by abnormal neuronal discharges with or without loss of consciousness. they very in cause, presentation, consequences, duration, and management
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Define epilepsy:
two or more unprovoked seizures; symptoms of disturbed electrical activity in the brain
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What are the ages of highest incidence of having a first seizure?
- under 2 years old
- over 65 years old
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name special populations which are at risk for epilepsy
- children with:
- mental retardation(26%)
- cerebral palsy (13%)
- both disablities (50%)
- alzheimer's patients (10%)
- stroke patients (22%)
- down syndrome (5-10%)
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Causes of seizures in neonates (<1 month)
- perinatal hypoxia and ischemia
- intracranial hemorrhage and trauma
- acute CNS infection
- metabolic disturbances (hypoglycemia, hypocalcemia, hypomagesemia, pridoxine deficiency)
- drug withdrawal
- development disorders
- genetic disorders
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causes of seizures in 1 month to 12 yo
- febrile seizures
- genetic disorders
- CNS infections
- developmental disorders
- trauma
- idiopathic
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causes of seizures in 12 to 18 yo
- trauma (drive)
- genetic disorders
- CNS infection
- brain tumor
- illicit drug use
- idiopathic
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cause of seizures in 18-35 yo
- trauma
- alcohol withdrawal
- illicit drug use
- brain tumor
- idiopathic
- pregnancy- eclampsia
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causes of seizures in adults >35 yo
- cerebrovascular disease
- brain tumor
- alcohol withdrawal
- metabolic disorders
- alzheimer's disease
- idiopathic
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Possible triggers for seizures
- elevated fever
- lack of sleep
- hormone fluctuations
- specific phase of the menstrual cycle
- flashing or flickering lights
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Pathophysiology of seizures
alterations in the disturbution, number, type and biophysical properties of ion channels in the nueonal membranes (Na, Ca, K)
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Name the types of partial seizures
- simple partial seizures
- complex parital seizures
- partial seizures with secondary generalization
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Types of primarily generalized seizures
- absence (petit mal)
- tonic-clonic (grand mal)
- atonic
- myoclonic
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Types of unclassified seizures
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Describe a simple partial seizure
- does not loose consciousness
- cause motor, sensory, autonomic, or psychic symptoms
- may begin in fingers and gradually progress to a larger portion of the extremity
- may allso manifest: somatic sensation, vision, equilibrium, flushing, sweating, hearing, smell, odd, internal feelings such as fear, illusions that objects are growing smaller or larger, deja vu
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Describe a complex partial seizure
- frequently begin with aura
- progress to the ictal phase, which may begin with a motionless stare
- loose consciousness
- typically confused following seizure, full recovery may be seconds to hours
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Describe a partial seizure with secondary generalization
- can spread to involve both hemispheres and produce a generalized seizure, usually of the tonic-clonic variety
- focal onset is not clinically evident and may be established only through careful patient hx and EEG anaylsis
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Describe a generalized absence seizure
- sudden, brief lapses of consciousness withough loss of postural control
- last for only seconds and returns suddenly
- often accompanied by subtle, bilateral motor signs such as rapid blinking of the eyelides, chewing movements, clonic movements of the hands
- usually begin in ages 4-8
- first clue = daydreaming
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Describe a generalized tonic-clonic seizure
- most common seizure type resulting from metabolic derangements
- usually begins withough warning
- inital phase = tonic contraction of muscles throughout the body, contraction of the jaw muscles may cause biting of the tongue
- tonic phase = repeated by jerks of the arms and/or legs
- posticital phase = unresponsiveness, excessive salivation
- bladder or bowel incontinence
- regain consciousness over minutes to hours, may have HA, fatigue, and muscle aches that lasts for hrs
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Describe an atonic seizure
- sudden loss of normal muscle tone, lasting 1-2 seconds
- consciousness is briefly impaired
- quick head drop
- collapse
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Describe a myoclonic seizure
- sudden and brief muscle contraction that may involve one part or the entire body
- muscle contractions causes jerks or twitches of the upper body, arms or legs
- most commonly associated with metabolic disorders, degenerative CNS disease, anoxic brain injury
- usually coexist with other forms of generalized seizure disorders, but are the predominant feature of juvenile myoclonic epilepsy
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Describe a febrile seizure
- arising in late infancy (18-24 months)
- occurs during the rising phase of the temperature and how rapidly in rises
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Describe an infantile spasms
- disorder of infancy and early childhood
- spasms are sudden, brief contractions (less than 10 seconds)
- usually involve muscles of the neck, trunk, and extremities, often occur in clusters
- some may be treated with ACTH or prednisone
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Diagnosis of epilepsy
- medical hx
- lab studies
- EEG
- brain scans (CT, MRI, PET, SPECT)
- developmental, neurological, and behavioral tests
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EEG
most common diagnostic test for epilepsy, can detect abnormalities in the brains electrical activity
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First line drugs for generalized tonic-clonic seizure
- valproic acid
- lamotrigine
- topiramate
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First line drugs for partial seizures
- carbamazepime
- phenytoin
- lamotrigine
- oxcarbazepine
- valproic acid
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First line drugs for absence seizures
- valproic acid
- ethosuximide
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First line drugs for myoclonic and atonic seizures
- valproic acid
- lamotrigine
- topiramate
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alternatives for tonic clonic seizures
- zonisamide
- phenytoin
- carbamazepine
- oxcarbazepine
- phenobarbital
- primidone
- felbamate
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alternatives for partial seizures
- levetiracetam
- topiramate
- tiagabine
- zonisamide
- gabapentin
- phenobarbital
- primidone
- felbamate
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alternatives for absence seizures
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alternatives for myoclonic,atonic seisures
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neurologic adverse effects of phenytoin
- dizziness
- nystagmus
- ataxia
- incorrdination
- confusion
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systemic adverse effects of phenytoin
- gum hyperplasia
- lymphadenopathy
- hirsutism
- osteomalacia
- skin rash
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drug interactions with phenytoin
- level increase by isoniazid, sulfonamides, fluoxetine
- level decreased by enzyme inducing drugs
- altered folate metabolism
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Neuological effects of carbamazepine
- ataxia
- dizziness
- diplopia
- vertigo
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systemic adverse effects of carbamazepine
- aplastic anemia
- leukopenia
- GI irritaion
- hepatotoxicity
- hyponatremia
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drug interactions with carbamazepine
- levels decreased with enzyme inducing drugs
- levels increased by erythromycin, propoxyphene, isoniazid, cimetidine, fluoxetine
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neurological adverse effects of valproic acid
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systemic adverse effects of valproic acid
- hapatotoxicity
- thromobcytopenia
- GI irritation
- pancreatitis
- weight gain
- transiet alopecia
- hyperammonemia
- cat x
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drug interactions with valproic acid
levels increased by enzyme inducing drugs
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neurological effects of ethosuximide
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systemic effects of ethosuximide
- GI irritation
- skin rash
- bone marrow suppression
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drug interactions with ethosuximide
valproic acid
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Neurological effects of phenobarbital (same with primidone)
- sedation
- ataxia
- confusion
- dizziness
- depression
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systemic effects of phenobarbital (same with primidone)
skin rash
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drug interactions with phenobarbital (same for primidone)
levels increased by valproic acid, phenytoin
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neurological effects with clonazepam
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systemic effects of clonazepam
anorexia
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drug interactions with clonazepam
levels drecreased by enzyme-inducing drugs
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neurological effects of lamotrigine
- dizziness
- diplopia
- sedation
- ataxia
- headache
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systemic effects of lamotrigine
- skin rash
- stevens-johnson syndrome
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drug interactions with lamotrigine
- level decreased by enzyme inducing drugs and oral contraceptives
- levels increased by valproic acid
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neurologic effects of gabapentin
- sedation
- dizziness
- ataxia
- fatigue
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systemic effects of gabapentin
- GI irritation
- weight gain
- edema
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drug interactions with gabapentin
no known significant interactions
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neurologic effects of levetiracetam
- sedation
- fatigue
- incooridation
- psychosis
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systemic effects of levetiracetam
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drug interactions with levetiracetam
none known
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neurologic effects with topiramate
- psychomotor slowing
- sedation
- speech or language problems
- fatigue
- paresthesias
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systemic effects of topiramate
- metabolic acidosis
- renal stones
- glaucoma
- weight loss due to anorexia
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drug interactions with topiramate
levels decreased by enzyme inducing drugs
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neurologic effects of oxcarbazepine
- fatigue
- ataxia
- dizziness
- diplopia
- vertigo
- headache
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systemic effects of oxcarbazepine
same as carbamazepine
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drug interactions with oxcarbazepine
- levels decreased by enzyme inducing drugs
- may increase phenytoin
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neurologic effects of tiagabine
- confusion
- sedation
- depression
- dizziness
- speech or language problems
- paresthesias
- psychosis
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systemic effects of tiagabine
GI irritation
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drug interactions with tiagabine
levels decrease by enzyme inducing drugs
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neurlogic effects of zonisamide
- sedatoin
- dizziness
- confusion
- headache
- psychosis
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systemic effects of zonisamide
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drug interactions with zonisamide
levels decreased by enzyme inducing drugs
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neurologic effects of felbamate
- insomnia
- dizziness
- sedation
- headache
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systemic effects of felbamate
- aplastic anemia
- hepatic failure
- weight loss
- GI irritation
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drug interactions with felbamate
increases phenytoin, valproic acid, active carbamazepine metabolite
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