Term
Phenytoin MOA?
Drug w/ same MOA? |
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Definition
Binds to inactivated Na channels (like class Ib antiarrhythmics) & keeps them inactivated --> prevents propagation
Carbamazepine |
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Term
| Lamotrigine/felbamate MOA |
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Definition
blocks voltage-gated Na+ channels
(felbamate blocks NMDA receptors) |
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Term
| two drugs used as adjunct therapy to other antiepileptics |
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Definition
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Term
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Definition
| inhibits Ca++ currents (originally designed as GABA analog) |
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Term
inhibits Ca++ currents (originally designed as GABA analog)
Used in peripheral neuropathic pain & bipolar disorder as well as S,C,&T-C seizures |
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Definition
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Term
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Definition
| Blocks Na+ channels (AMPA & increases GABA action |
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Term
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Definition
- Blocks inactivated Na+ channels (like phenytoin
- inhibits GABA transaminases (increase GABA)
- blocks T-type Ca++ channels |
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Term
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Definition
Blocks thalamic T-type Ca++ channelos
(block presynaptic Ca++ influx through T-type Ca++ channels ) |
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Term
| 2 drugs that block presynaptic Ca++ influx through T-type Ca++ channels |
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Definition
| Valproic acid & ethosuximide --> used for absence seizures |
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Term
| Describe T-type Ca++ channels |
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Definition
Low voltage activated channels throught brain.
The "T" stands for "transient" since they are inactivated/reactivated after depolarization/repolarization
They are also in pacemaker cells of heart (along with If "funny" channels) & tonic bursting of thalamus (along w/ H "funny" channels); in both cases, the T-type Ca++ channel causes the spike |
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Term
| drugs working directly on GABAa receptor (3) |
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Definition
Barbiturates
Benzodiazepines
Ethanol |
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Term
| GABAb receptor selective drugs |
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Definition
| Baclofen (used for spasticity) |
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Term
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Definition
Topiramate
also increases GABA action |
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Term
| This antiepileptic drug blocks NMDA |
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Definition
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Term
| used in manic phase of bipolar |
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Definition
| Carbamazepine & valproic acid |
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Term
| antiseizure drug that inhibits p450 |
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Definition
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Term
| antiseizure drug that induces p450 |
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Definition
| all of them except valproic acid (inhibits) |
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Term
| Don't take EtOH, ddI, ddC, or asparaginase w/ this drug |
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Definition
| valproic acid (all these things can cause pancreatitis) |
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Term
| heptatotoxicity, thrombocytopenia, pancreatitis, alopecia, & spina bifida |
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Definition
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Term
teratogenicity of:
Valproic acid
Phenytoin
Carbamazepine |
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Definition
Spina bifida
Cleft lip/palate
Both spina bifida & cleft lip/palate |
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Term
| Verapimil, diltiazam & nefedipine block this type of channel |
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Definition
| L-type Ca++ channel (phase 2 of cardiac AP; smooth muscle) |
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Term
| This type of Ca++ channel is found in abundance in the thalamus & SA node |
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Definition
| T-type Ca++ channel (pacemaker) |
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Term
| Didplopia, ataxia, p450 induction, teratogenicity |
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Definition
SE common to Carbamazepine & Phenytoin
unique SE:
-Carbamazepine: SJS, agranulocytosis & aplastic anemia, SIADH
- Phenytoin:Gingival hyperplasia in kids, SLE-like syndrome, hirsutism, 0-order elimination, decreased folate (megaloblastic anemia) |
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Term
| Things you can use Carbamazepine for that you can't use Phenytoin for? |
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Definition
| neuropathic pain & manic bipolar |
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Term
| Things you can use phenytoin for but not carbamazepine? |
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Definition
DIG toxicity (FAB is 1st line)
(also, Mg++ & lidocaine can be used) |
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Term
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Definition
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Term
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Definition
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Term
| Name Carbamazepine SE (8) |
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Definition
- Diplopia
- Ataxia
- Blood dyscrasias (agranulocytosis & aplastic anemia)
- liver toxicity
- teratogenesis (spina bifida & cleft lip/palate)
- induces p450 (induces own metabolism --> need higher and higher doses)
- SIADH
- Osteomalacia |
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Term
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Definition
- Carbamazepine
- Phenytoin
- Lamotrigen
(other non-epilepsy drugs: penicillins, OSU, sitagliptin, HIV drugs)
(prodome of malaise & fever followed by rapid onset of erythematous/purpuric macules (oral, ocular, genital) --> progress to epidermal necrosis & sloughing |
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Term
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Definition
EFGH
Ethosuximide
GI distress
Fatigue
Headache |
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Term
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Definition
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Term
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Definition
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Term
| reduces absorption of folate |
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Definition
| phenytoin (inhibits intestinal folate conjugases) |
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Term
| teratogenicity of phenytoin, valproic acid, and carbamzepine |
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Definition
Valproic Acid: spina bifida
Phenytoin: Cleft lip/palate
Carbamazepine: both |
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Term
| binds Beta unit on GABA receptor |
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Definition
| barbiturates (can activated it alone, or increase duration of activation by GABA) |
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Term
| inducer of many p450s & thus interacts w/ many drugs |
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Definition
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Term
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Definition
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Term
| Contraindicated in porphyrias |
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Definition
barbiturates (any p450 inducer is)
(barbiturates induce d-ALA synthase (B6-dependent first step) |
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Term
| where do you get succinyl COA? |
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Definition
| VOMIT pathway: valine, odd-chain fatty acids, methionine, isoleucine, threonine |
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Term
| Tx overdose w/ barbiturates |
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Definition
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Term
| how did Heath Ledger die? |
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Definition
| taking antihistamines & some other GABAa drug (these are additive effects) --> severe respiratory depression |
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Term
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Definition
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Term
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Definition
sedation (general)
mental dulling (general)
Kidney stones (specific to topiramate)
weight loss (specific) |
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Term
| mechanism of megaloblastic, aplastic anemias, & osteomalacia w/ phenytoin use |
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Definition
megaloblastic: inhibit intestinal folate conjugases --> folate deficiency
Aplastic: hypersensitivity from hapten formation --> RBC destruction (can also see leukopenia)
Osteomalacia: decreases VitD (?defect in 25 hydroxylase) |
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Term
| Name stages of GABA analog use. What is the peak for each? |
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Definition
1) paroxysmal dysinhibition
2) sedation, anxiolytic, anticonvulsant
3) Hypnosis
4) Anesthesia
5) Medullary depression
6) coma & death
Benzos peak around 3-4
EtOH & barbiturates don't peak
need respiratory support in >3 |
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Term
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Definition
| Flumazenil (blocks BZ1 & BZ2 receptors) |
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Term
| Benzos not liver metabolized? |
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Definition
| Lorazepam (most important), oxazepam, temazepam |
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Term
| GABA acting drug w/ least chance of respiratory depression |
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Definition
| Benzos (vs barbiturates & EtOH) |
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Term
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Definition
| TOM: triazolam, oxazepam, & midazolam (first 2 used for insomnia) |
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Term
| used for insomnia w/ less tolerance & addiction than benzos |
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Definition
BZ1 receptor agonists
Zolpidem, Zaleplon, Eszoplicone |
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