Term
| Seizures are believed to involve the ___ and ___, and not ___, ___, or ___. |
|
Definition
Cerebral cortex and limbic system
Thalamus, brainstem, or cerebellum |
|
|
Term
| The therapeutic index for most antiseizure meds is ___, and ___ |
|
Definition
Low
Toxicity is not uncommon |
|
|
Term
| Absence/petit mal seizure |
|
Definition
Brief loss of awareness
May have eye blinking or lip-smacking
No loss of consciousness or body tone
Usually in kids
T currents and 3Hz spike and wave |
|
|
Term
|
Definition
Epileptic syndrome not a seizure type
Brief, recurrent myoclonic jerks
Patients are usually mentally retarded |
|
|
Term
|
Definition
|
|
Term
| Benzos are good for all ___ seizures except ___ |
|
Definition
|
|
Term
| DOC tonic-clonic seizures (2) |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Tx for trigeminal neuralgia |
|
Definition
|
|
Term
| Broadest spectrum antiseizure meds (2) |
|
Definition
|
|
Term
| 2nd line drug for absence seizures |
|
Definition
| Lamotrigine (if the patient can't tolerate DOC ethosuximide) |
|
|
Term
|
Definition
Corticotropin/ACTH
Usually refractory to antiseizure meds |
|
|
Term
| Tx generalized tonic-clonic and partial seizures (6) |
|
Definition
Carbamazepine
Phenytoin
Ethotoin
Phenobarbital
Gabapentin
Topiramate |
|
|
Term
| DOC status epilepticus (2) |
|
Definition
|
|
Term
| 2nd line drug for status epilepticus |
|
Definition
| Fosphenytoin (if DOCs diazepam/lorazepam are ineffective) |
|
|
Term
| Seizures can result from ___ or ___ |
|
Definition
Excessive excitation
Decreased inhibition |
|
|
Term
| Mechanisms to inhibit excitation (2.2) |
|
Definition
Block glutamateR
Alter ion channel conductance
-prolong Na-channel inactivation state = reduce frequency neurons can generate repetitive AP
-reduce low threshold Ca currents = implicated in 3Hz spike-wave of absence seizures |
|
|
Term
| Mechanisms to enhance inhibition |
|
Definition
Act at allosteric binding sites on GABA-R to enhance GABA-mediated chloride conductance
Stimulate glutamic acid decarboxylase to make more GABA
Increase release of GABA
Inhibit degradation of GABA |
|
|
Term
| Antiseizure meds pharmacokinetics (5) |
|
Definition
Absorption is good (except phenytoin, carbamazepine)
Not highly bound to plasma proteins
Converted to active metabolites by liver
Cleared by liver = drug interactions
Plasma clearance is slow = long-acting |
|
|
Term
| Drugs eliminated by renal excretion |
|
Definition
|
|
Term
| Drugs that compete for hepatic enzymes will ___, but with chronic use will ___ |
|
Definition
Decrease metabolism of each other
Increase metabolism of each other and vitamins |
|
|
Term
| Drugs that prolong Na-channel inactivation state (7) |
|
Definition
Phenytoin
Fosphenytoin
Ethotoin
Valproate
Carbamazepine
Lamotrigine
Topiramate |
|
|
Term
| Phenytoin is not effective for ___ |
|
Definition
|
|
Term
| Other drug for status epilepticus |
|
Definition
|
|
Term
| Phenytoin: indications (2) |
|
Definition
Generalized tonic-clonic seizures
Partial seizures
NOT absence seizures |
|
|
Term
| For phenytoin, liver enzymes are ___ at therapeutic doses, therefore a ___ will ___ |
|
Definition
Near saturation
Small increase in dosage
Large increase in plasma-phenytoin |
|
|
Term
|
Definition
Hirsutism
Gingival hyperplasia (serious!)
Osteomalacia (responsive to vitD)
Megaloblastic anemia (responsive to folate) |
|
|
Term
| Fosphenytoin (water-soluble prodrug of phenytoin): indications (3) |
|
Definition
Status epilepticus
Prevention/tx seizures during neurosurgery
Short-term substitute for oral phenytoin |
|
|
Term
| Ethotoin: indications (3) |
|
Definition
Generalized tonic-clonic seizures
Complex partial seizures
Phenytoin-alternative in kids b/c lacks phenytoin's other S/E |
|
|
Term
|
Definition
| Blood dyscrasia (monitor!) |
|
|
Term
| Valproate: indications (4) |
|
Definition
Atonic seizures
Myoclonic seizures
Absence seizures
Multiple seizure types |
|
|
Term
|
Definition
Hepatotoxicity due to toxic intermediates, especially with other antiseizure meds
Worry about this especially in kids |
|
|
Term
| Carbamazepine: indications (3) |
|
Definition
Partial seizures
Generalized tonic-clonic seizures
Trigeminal neuralgia
NOT absence seizures |
|
|
Term
|
Definition
Bone marrow depression: leukopenia, aplastic anemia, agranulocytosis (monitor!)
Hyponatremia (monitor!)
Water retention = prob for older patients with heart disease
Also monitor hepatic function |
|
|
Term
| Lamotrigine: indications (4) |
|
Definition
Partial seizures
Generalized seizures
Absence seizures
Refractory partial seizures |
|
|
Term
| Topirimate: indications (2) |
|
Definition
Refractory partial seizures
Generalized tonic-clonic seizures |
|
|
Term
| Tx refractory partial seizures (2) |
|
Definition
|
|
Term
| Topiramate: S/E, excretion by ___ |
|
Definition
Cognitive impairment
Excretion by kidneys unchanged |
|
|
Term
| Drugs that reduce low-threshold Ca currents (2) |
|
Definition
|
|
Term
| Ethosuximide: indications, S/E |
|
Definition
Absence seizures
Bone marrow depression, blood dyscrasias: aplastic anemia, leukopenia, thrombocytopenia, SLE |
|
|
Term
|
Definition
Prolong Na-channel inactivation state
Reduce low-threshold Ca currents
Stimulates glutamic acid decarboxylase to make more GABA
Inhibits degradation of GABA |
|
|
Term
| Drug that blocks glutamateR |
|
Definition
|
|
Term
|
Definition
Prolong Na-channel inactivation state
Block glutamateR (kainateR antagonist)
Increase release of GABA |
|
|
Term
| Drugs that enhance GABA-mediated chloride conductance (2) |
|
Definition
Phenobarbital
Benzos (-pam) |
|
|
Term
|
Definition
| Increases duration of GABA-channel opening |
|
|
Term
| Phenobarbital: indications (2) |
|
Definition
Generalized tonic-clonic seizures
Partial seizures
NOT absence seizures |
|
|
Term
| Maximal antiseizure action of phenobarbital is at doses below ___ |
|
Definition
| Those required for hypnotic effects |
|
|
Term
| Phenobarbital: pharmacokinetics (3) |
|
Definition
t1/2 influenced by lipid solubility, which determines rate of redistribution from brain to skeletal muscle/adipose tissue and contributes to the termination of CNS effects
-Phenobarbital = less lipid soluble = longer-acting
-Redistribution, not metab, produces the ultrashort hypnotic action of highly lipid-soluble barbiturates
Clearance requires hepatic transformation to water-soluble form
-alterations in hepatic function (disease, age, other drugs) influence rate of phenobarbital metabolism and duration of action
Increase excretion by alkalinizing urine = useful for barbiturate overdose (but only in long-acting ones that have pKa ~7.2) |
|
|
Term
|
Definition
Long-term use at high doses (induces CYP450)
Osteomalacia (responsive to vitD)
Megaloblastic anemia (responsive to folate)
Hemorrhage in newborn if mom's on the drug (responsive to vitK)
Porphyria |
|
|
Term
| Barbiturates combined with other depressant causes ___ |
|
Definition
|
|
Term
|
Definition
| Increase the frequency of GABA channel opening |
|
|
Term
|
Definition
|
|
Term
| Drug that stimulates glutamic acid decarboxylase to make more GABA |
|
Definition
|
|
Term
| Drugs that increase release of GABA (2) |
|
Definition
|
|
Term
|
Definition
|
|
Term
| Gabapentin: indications (3) |
|
Definition
Adjunct tx for partial seizures
Adjunct tx for generalized tonic-clonic seizures
Postherpetic neuralgia |
|
|
Term
| Gabapentin: excretion, S/E (2) |
|
Definition
Excreted unchanged by kidneys
Dizziness
Drowsiness |
|
|
Term
| Drug that inhibits degradation of GABA |
|
Definition
|
|
Term
| Drugs that cause cognitive impairment (6) |
|
Definition
Phenytoin
Phenobarbital
Carbamazepine
Topiramate
Valproate
Benzos |
|
|
Term
| Drugs that don't cause cognitive impairment (2) |
|
Definition
|
|
Term
| Prego categories for phenytoin/carbamazepine/valproate and gabapentin |
|
Definition
Phenytoin, carbamazepine, valproate: D
Gabapentin: C |
|
|
Term
| Drugs that don't decrease the effectiveness of OCPs (3) |
|
Definition
Lamotrigine
Gabapentin
Valproate |
|
|
