Epilepsy Flashcards
social impact of having epilepsy
patients can't drive poor school attendance low education cognitive difficulties multiple financial difficulties often don't have health insurance dependant on caregivers to assist with medications, transport, and ensuring safety
causes of epilepsy
underlying cause is unknown
most common cause is head trauma or stroke
other are genetic deficits, CNS tumors, CNS infections, neurodegenerative diseases, HIV, neurocysticercosis infections
causes of isolated seizures
stroke CNS trauma CNS infections metabolic disturbances (hyponatremia hypoglycemia) hypoxia
drugs that may cause seizures
tramadol bupropion theophylline some antidepressants some antipsychotics amphetamines cocaine imipenem lithium excessive doses of penicillins or cephalosporins sympathomimetics stimulants
NTs implicated in the pathophysiology of seizures
glutamate and GABA
Tonic-clonic seizures
primary generalized seizure sudden loss of consciousness tonic extension and rhythmic clonic contractions of major muscle groups lasts 1-3 minutes also called "grand mal" seizures
Absence seizures
Primary generalized seizure sudden and brief loss of consciousness without muscle movements last several seconds described as daydreaming or blanking out also called "petit mal"
Myoclonic seizures
Primary generalized seizure
single and brief jerk of all major muscle groups
patients may not lose consciousness
lasts less than 3-4 seconds
described as shoulder shurgs or spinal chills
may cluster and build into general tonic-clonic seizures
atonic seizures
primary generalized seizure
loss of consciousness and muscle tone
no muscle movements typically noted, patient goes limp
described as falling out
simple partial seizure
sensation of uncontrolled muscle movement of a portion of the body
no alteration of consciousness
dependent on location of seizure in brain
Complex partial seizure
localized in specific area of the brain
still an alteration in patient’s level of consciousness
secondarily generalized seizures
partial seizure
starts as a simple or complex partial seizure
spreads to involve entire brain
patient may report a warning or aura at the start of the seizure
Juvenile myoclonic epilepsy
Primary generalized epilepsy syndrome
usually starts in early to middle teenage years
strong familial component
myoclonic jerks and tonic-clonic seizure may also have absence seizures
Lennox-Gastaut seizures
cognitive dysfunction and mental retardation
usually consists of combination of tonic-clonic, absence, atonic, and myoclonic seizures
Mesial temporal lobe sclerosis
seizures consist of partial seizures arising from mesial temporal lobe of the brain
often associated with anatomical changed, described as hippocampal sclerosis
patients often have excellent surgical outcomes
Infantile spasms
occurs in infants less than 1 year old
characterized by specific EEG pattern and spasms or jitters
also knows as West’s syndrome
infants often develop other seizure types later in life
disorders that may be mistaken for seizures
convulsions syncope psychogenic nonepileptic events (pseudoseizures) anxiety attacks cardiac arrhythmias hypoglycemia TIA tics complicated migraine headaches
michaelis-menten metabolism
the maximum capacity of the hepatic enzymes is reached in the normal dose range
causes small changes in dose to create large jumps in serum concentrations
increased risk of sudden toxicity and side effects
which drug follows Michaelis-Menten metabolism?
phenytoin
How to adjust phenytoin doses
serum concentrations >7mcg/mL, increase total daily dose by 100mg
Concentrations between 7 and 12, increase by 50mg
Concentrations >12, increase by no more than 30mg
highly protein bound AEDs
phenytoin, tiagabine, VPA, carbamazepine, and clonazepam
populations with decreased protein binding
kidney failure hypoalbuminemia neonates pregnant women those taking multiple highly protein bound drugs patients in critical care
which AED is an autoinducer?
carbamazepine
Drugs recommended for tonic-clonic seizures
carbamazepine lamotrigine oxcarbazepine phenobarbital phenytoin topiramate VPA
