AED Flashcards
Mechanism of action of Rufinamide
Prolong the inactivation state of Na channel
Phenobarbital drug that can be used in insomnia
secobarbital
Protein binding of PB
70%
Can be used in Lennox Gastaut Syndrome
Felbamate
oral source of lacosamide
Phenylalanine
Half life of Zonisamide
1-3 days
What are the mechanism of action of lamotrigine
Blockade of Na channel
Inhibit voltage Ca channel (N & P/Q Type)
Decrease synaptic release of glutamate
This AED is similar to imipramine
Carbamazepine
Maximum dose of Levetiracetam
3000mg/d
This AED is an Sulfonamide derivatives
Zonisamide
What drug increases its level when given lamotrigine
VPA
Clinical use of phenytoin
Partial and generalized seizure (primary and secondary)
Elimination of Phenytoin
First order kinetics
Felbamate may cause this toxicity
Aplastic anemia
Hepatitis
Peak level of CBZ is achieved at
6-8hours
Half life of Vigabatrin
6-8 hours
Effective plasma level of Felbamate
30-100mg/ml
Elimination of Gabapentin
Renal
Volume of distribution of PB
0.6L/kg
Half lite of phenytoin
12-36h
Drug interaction of Felbamate
Increase level of PHT and VPA
Decrease CBZ
This AED is a substituted monosaccharide
Topiramate
Peak concenration of lacosamide
1-4 hours
If sulfonamide is added with phenytoin what will happen?
Displaces phenytoin from protein increasing its free drug concentration
AE of VPA
Elevation of liver profile, thrombocytopenia, hyperammonemia, spina bifida
Protein Binding of CBZ
70%
Absorption of Phenytoin in GI
Complete at 3-12 hrs
Most common toxicity of CBZ
Diplopia and ataxia
Half life of perampanel
70-110 hours
What AED has an antifolate activity
Lamotrigine
Drug interaction of ethosuximide
VPA decreases ETX
Bioavailability of lacosamide
100%
Half-life of lacosamide
13 hours
Half life of rufinamide
6-10 hours
Protein binding of VPA
90%
What is the metabolite of Primidone
Pb –> PEMA
What drug makes topiramate less effective
OCP
Mechanism of action of VPA
- Blocks NMDA receptor mediated excitation
- Increases GABA
- facilitates glutamic acide decarboxylase (for GABA synthesis)
- Potent inhibitor of histone deacetylase
Volume of distribution of VPA
0.15 L/kg
What is the mechanism of action of Lacosamide
Enhances slow inactivation voltage gated Na channel
Binds to CRMP blocks BDNF and NT-3
What is the metabolite of Oxcarbazepine and its halflife
Eslicarbazepine
8-12 hours
Metabolism of Stiripentol
Inhibitor of CYP3A4 CYP1A2 and CYP 2C19 (increase the level of other AED)
half-life of lamotrigine
24 hours
Toxicity of Phenytoin
Nystagmus Ataxia Diplopia Hirsutism Hyperplasia of gingiva Coarse facial Osteomalacia Decreased DTR NADH2COD
Excretion of Phenobarbital is enhance by
Alkalinization of urine
This is an triazole derivatives
Rufinamide
This congener of phenytoin causes dermatitis, aggranulocytosis and hepatitis
Mephytoin
Mechanism of action of Perampanel
Acts at post synaptic AMPA receptor that shortens the repetitive discharge of neuronal system
Mechanism of action of Stiripentol
Enhances GABAergic transmission of Cl channel and GAB-A receptor
Mechanism of action of pregabalin and gabapentin
α2δ subunit-containing voltage-gated calcium channels
What is the mechanism of action of Phenobarbital (4)
Prolong opening of Cl channel (main)
Allosteric modulator on GABA-A
Suppress high frequency of Na conductance
At high dose: blocks L and N Type Ca Channel
Adverse effect of Retigabine
Decrease visual activity
Blue skin discoloration (Potiga)
Clinical use of topiramate
- monotherapy for partial and GTC
- LGS
- Infantile spasm and absence
- migraine
Adverse effect of Vigabatrin
irreversible visual field defect
What is the mechanism of action of Zonisamide
- reduces the low threshold of Ca T-type channel
Clinical use of CBZ
Partial and GTC seizure
Trigeminal neuralgia
Bipolar disorder
Mechanism of action of Retigabine
K channel facilitator
What is the mechanism of action of Levetiracetam
Binds to synaptic vesicle (SV2A)
What is the advantage of Eslicarbazepine
once daily dosing
Mechanism of action of OXazolidonedione
Raises threshold for seizure discharge after repetitive thalamic stimulation
Therapeutic level of CBZ
1-2g
Indication for acetazolamide
Catamenial Sz
TD of PB
15-30mcg/ml
Indication of Gabapentin
postherpetic neuralgia
adjunct in GTC and Partial Sz
Adverse effect of perampanel
behavioral adverse reaction
What is improved in Oxcarbazepine
Toxicity profile
Half life of ethosuximide
40 hours
Clinical uses of Ethosuximide
Absence Seizure (Drug of choice)
AE of topiramate
Hypospadias
Urolithiasis
Glaucoma
Mechanism of action of Felbamate
NMDA receptor NRI-2B
Barbiturate like potentiation of GABA-A receptor
What test should be done if patient is on Phenytoin?
Thyroid function test (has affinity with thyroid binding globulin)
Mechanism of action of Zonisamide
- Blocks Na CHannel
2. Acts on T type voltage gated Ca Channel
Protein binding of perampanel
95%
Indication of Pregabalin
Partial Sz +/- secondary generalization
Fibromyalgia
Anxiety Disorders
Protein binding of topiramate
15%
Clinical use of Stirpentol
Adjunct with clobazam and VPA for refractor GTC
Myoclonic epilepsy of infanct (SMEi, Dravets)
Half life of VPA
9-18 hours
Protein binding of Pregabalin
None
Volume of distribution of lamotrigine
1-1.4L/Kg
Anticonvulsant metabolite of CBZ
11-epoxide
Half-life of levetiracetam
6-8 hours
Half life of topiramate
20-30 hours
Drug interaction of perampanel
Induces CBZ and PHT
When use with CBZ - half life is reduced to 25 hours
Mechanism of action of Tiagabine
inhibitor of GABA uptake
Inhibit GAT-1 than GAT 2 and 3
Increase intracellular GABA
This makes eslicarbazepine less effective if given with this drug
Oral contraceptives
What is the antiseizure agent of Phenobarbital
Barbituric Acid
Halflife of Phenobarbital
4-5 days
Mehanism of action of CBZ
Blocks Na
Potentiate K
Therapeutic level of ethosuximide
60-100mcg/ng
Protein binding of Levetiracetam
10%
Peak concentration of VPA
2 hours
AE of Zonisamide
Cognitive impairment
CLinical use of lamotrigine
Adjunct therapy
monotherapy for partial Sz,
Absence sz, LGT
Bipolar disorders
Drug interaction of CBZ
Increase matanolism of PHT ETX and VPA
Increase staeady state of VPA
Decrease steady state of PHT and PBZ
Mechanism of action of Topiramate
- Blocks voltage gated Na channel
- Potentiate inhibitory effect of GABA
- Depress action of Kainate on glutamate receptor
Half life of Gabapentin
5-8 hours
This drug enhances the effect of GABA by irreversibly inhibiting GABA-aminotransferase
Vigabatrin
Pharmacodynamics of Retigabine
Linear kinetics and absorption is not affected by food
Phenobarbital can worsen this type of seizure
Absence
Infantile spasm
Half-life of Tiagabine
5-8 hours
Drug interaction of VPA
- Inhibit metabolism of Pb PHT and CBZ
Mechanism of action of Phenytoin
Prolingation of inactivated Na channel
Blocks the persistence of Na channel
Decrease Ca permeability
Acetazolamide exerts its antiSz activity by
mild acidosis
Clinical indication of Phenobarbital
GTC and partial Seizure
Elimination half-life of stiripentol
Non-linear kinetics
Therapeutic level of VPA
25-30mg/kg/day