CH 22: Seizure Medications Flashcards
What is the choice of antiepileptic drug therapy (AED) dependent on?
- dependent on seizure type and characteristics
- medical hx
- results of EEG & other diagnostic tests
- cormorbid conditions
- never stop taking without guidance of HCP - can cause withdrawal seizures
NEED TO KNOW!!!
Benzodiazepines - how & what are they used for?
how do they work for seizures?
- most important drugs in treatment of status epilepticus
- control seizures by acting in limbic, thalamic, hypothalamic regions of CNS
- limited applications (use for seizures when other drugs ineffective)
- have resuscitation equipment available if administering by IV - monitor for CV collapse & resp depression
NEED TO KNOW!!!
What are some considerations for benzodiazepines?
- educate on s/s resp depression + cv collapse
- assess for decr in seizure activity
- maintain pt safety pre & post seizures (watch for triggers)
- assess for hx of smoking (may req larger doses)
- assess for urinary retention
- don’t mix with other drugs parenterally
NEED TO KNOW!!!
Hydantoins - what are they used for?
- most effective in management of most types of seizures, including general seizure, but have many AEs
- desensitize sodium channels
hydantoin - prototype drug?
phenytoin (dilantin, phenytek)
- therapeutic: antiepileptic
- pharmacologic: hydantoin, neuronal sodium channel modulator
use = prophylactic therapy of all seizures except absence
mechanisms of action: delays influx of sodium ions in neurons, doesn’t elevate seizure threshold
dibenzazepines - what are they for?
- drug of choice for many tonic-clonic and partial seizures
- acute mania
- off-label: symptomatic treatment of neuropathic pain, hiccups, severe symptoms of dementia
Phenytoin - any considerations?
NEED TO KNOW!!!
- shake suspension well prior to administration
- watch for extravasation with IV route
- check bld levels regularly (like lithium, dig, tegretol)
- monitor CBC (clotting)
- watch for neurological changes & SE
- monitor bld glucose in diabetics
- assess folic acid deficiency
dibenzazepines - prototype drug?
carbamazepine (carbatrol, tegretol, others)
- t = antiepiletic drug
- p = iminostilbene, neuronal sodium channel modulator
- inhibits sodium channels, blocks repetitive, sustained firing of neurons
carbamazepine - any contraindications/precautions?
dibenzazepines
NEED TO KNOW!!!
- hypersensitivity
- increased ocular pressure
- lupus
- cardiac/hepatic disease
- HTN
- older adults (watch narrow safety margin)
- pregnancy - category D
Valproic acid - what is it?
valproic acid (Depacon, Depakene, Depakote)
- anti-epileptic drug, anti-manic agent; GABA agonist
- for absence seizures/complex partial seizures; mania; migraine
- incr conc of GABA in brain
valproic acid - what are the drug interactions?
- additive sedation w/ CNS depressants & alcohol
- more rapid metabolish w/ enzyme-indcuing AEDs
- incr serum levels of TCAs
- incr serum levels w/ aspirin, isoniazid, cimetidine (watch for bleeding)
- decr absorption w/ cholestyramine
- binds with some fat-soluble vitamins
what are some considerations w/ valproic acid?
NEED TO KNOW!!!
- monitor seizure activity & check serum levels
- obtain baseline platelet counts & check PT/PTT/INR regularly during therapy
- monitor for s/s hyperammonemia & bleeding
- watch liver lab work
- naloxone & hemodialysis for overdose treatment
