Chapter 71: Seizures/Epilepsy Flashcards
1
Q
What is the most common test used to diagnose epilepsy
A
EEG
2
Q
Key drugs that can lower the seizure threshold
A
Bupropion Clozapine Theophylline Varenicline Carbapenems (esp. imipenem) Lithium Meperidine Penicillin Quinolones Tramadol
3
Q
Where does a focal seizure start
A
One side of the brain, but can spread to the other side
4
Q
Where does a generalized seizure start
A
Both sides of the brain
5
Q
If a focal seizure results in no loss of consciousness, it is called
A
focal aware seizure
6
Q
If a focal seizure results in loss of consciousness, it is called
A
focal seizure with impaired awareness
7
Q
What are tonic symptoms
A
rigid or tense muscles
8
Q
Generalized seizures with non-motor symptoms are called
A
absence seizures
9
Q
What is status epilepticus
A
A seizure that lasts beyond 5 minutes. It is a medical emergency
10
Q
What are the 3 phases of status epilepticus called and what are the time intervals for them
A
0-5 minutes = stabilization period
5-20 minutes = initial treatment phase
20-40 minutes = second treatment phase
11
Q
What should be done during the stabilization phase of SE
A
Time the seizure
Start EEG, oxygen may be needed
Check AED levels, electrolytes, if BG low - treat with D25-D50
12
Q
What should be done during the initial treatment phase of SE
A
If seizure continues:
Give IV lorazepam (Ativan)
Alternatives if IV unavailable: IM midazolam (Versed) or rectal diazepam (Diastat)
13
Q
What should be done during the second treatment phase of SE
A
If seizure continues:
Give regular AED: IV fosphenytoin, valproic acid, levetiracetam (phenobarbital if others are unavailable)
14
Q
Diastat AcuDial packages contain two rectal syringes prefilled with diazepam rectal gel. What doses does it come in
A
2.5, 10 and 20 mg
15
Q
How do you use Diastat AcuDial
A
- Syringes must be dialed to the right dose and locked BEFORE DISPENSING
- Once locked, the green band should say “READY,” and the syringe cannot be unlocked
16
Q
CBD brand name for seiures
A
Epidiolex
17
Q
What kind of diet can be used in patients with refractory seizures
A
Ketogenic
18
Q
What is the ratio of fats to protein and carbs in a ketogenic diet
A
4:1
19
Q
What medication is used for absence seizures
A
ethosuximide
20
Q
What is the MOA of benzodiazepines
A
Increases GABA
21
Q
What is the MOA of Valproic acid
A
Increases GABA
22
Q
What is the MOA of ethosuximide
A
T-type Ca channel blocker
23
Q
What is the MOA of carbamazepine
A
Na channel blocker
24
Q
What is the MOA of phenytoin/fosphenytoin
A
Na channel blocker
25
Which neurotransmitters are responsible for causing a seizure
```
Deficiency in GABA (inhibitory NT)
Excess glutamate (excitatory)
```
26
Side effects of carbamazepine, oxcarbazepine, and eslicarbazepine
hyponatremia, rash, enzyme inducers
27
Side effects of gabapentin and pregabalin
Weight gain, peripheral edema, mild euphoria
28
Side effects of phenobarbital and primidone (prodrug of phenobarbital)
Sedation, dependence/tolerance/OD risk, enzyme inducers
29
Side effects of topiramate and zonisamide
Weight loss, metabolic acidosis
| Nephrolithiasis and oligohydrosis/hyperthermia (in children)
30
All AEDs should be supplemented with
calcium and vitamin D
31
Women of childbearing age should supplement with ___ while on AEDs
folate
32
If taking valproic acid, what should you supplement with
possibly carnitine
33
If taking lamotrigine and valproic acid, what should you supplement with if alopecia develops
Selenium and zinc
34
Lamotrigine brand name
Lamictal
35
Lamotrigine dose for weeks 1 and 2
25 mg daily
36
Lamotrigine boxed warning
Serious skin reactions including SJS/TEN
37
Lamotrigine side effect
Alopecia (supplement selenium and zinc)
38
Lamictal starter kits are used to ensure correct dosing. Which color is the standard starting dose? When should you use it?
Orange
| Use if no interacting medications
39
Lamictal starter kits are used to ensure correct dosing. Which color is a lower starting dose compared to the others? When should you use it?
Blue
| Use if taking valproic acid (enzyme inhibitor)
40
Lamictal starter kits are used to ensure correct dosing. Which color is a higher starting dose compared to the others? When should you use it?
Green
| Use if taking an enzyme inducer (e.g., carbamazepine, phenytoin, phenobarbital, primidone), and not taking valpoic acid
41
Lamotrigine drug interactions
Valproic acid increased lamotrigine concentrations more than two-fold. Use lower starting dose (blue box)
Inducers like carbamazepine, phenytoin, phenobarbital, & primidone decrease lamotrigine concentrations by 40%. Use the higher starting dose (green box)
42
Levetiracetam brand name
Keppra, Keppra XR
43
Keppra IV:PO ratio
1:1
44
Keppra warnings
psych reactions, including psychotic symptoms, somnolence, fatigue
45
T/F: Keppra does not have any significant drug interactions
True
46
Topiramate brand name
Topamax
47
Another use for topiramate
Migraine ppx
48
Topiramate warnings
Metabolic acidosis, oligohydrosis (reduced perspiration), nephrolithiasis (kidney stones), angle-closure glaucoma, hyperammonemia, fetal harm
49
Topiramate side effects
Somnolence, difficulty with memory/concentration/attention, weight loss, anorexia
50
Topiramate monitoring
electrolytes (especially bicarbonate), intraocular pressure
51
Topiramate drug interaction
Can decrease OC effectiveness. Non-hormonal contraception is recommended
52
Valproic acid brand name
Depakene
53
Divalproex brand name
Depakote, Depakote ER, Depakote Sprinkle
54
Another use of divalproex
Bipolar and migraine ppx
55
Valproic acid therapeutic range
50-100 mcg/mL (total level)
56
Valproic acid boxed warning
hepatic failure, fetal harm (neural tube defects and low IQ scores)
57
Valproic acid warnings
Hyperammonemia (treat with carnitine in symptomatic adults only), thrombocytopenia (increased bleeding risk)
58
Valproic acid side effects
Alopecia (supplement selenium and zinc), weight gain
59
Valproic acid monitoring
LFTs (baseline and frequently in the first 6 months), platelets
60
What is the drug interaction between valproic acid and lamotrigine
risk of serious rash
61
Carbamazepine brand name
Tegretol, Tegretol XR
62
Carbamazepine therapeutic range
4-12 mcg/mL
63
Carbamazepine boxed warnings
Serious skin reactions: patients of Asian descent should be tested for HLA-B*1502 allele prior to initiation
Aplastic anemia and agranulocytosis
64
Carbamazepine contraindications
Myelosuppression
65
Carbamazepine warnings
hyponatremia (SIADH), fetal harm
66
Carbamazepine monitoring
CBC with diff and platelets, electrolytes (especially Na)
67
Carbamazepine drug interactions
Enzyme inducer, autoinducer - decreases levels of other drugs and itself
68
Which drugs can decrease levels of OCs and non-hormonal contraceptive is recommended
Topiramate, carbamazepine, oxcarbazepine, phenobarbital, primidone, phenytoin
69
Lacosamide brand name
Vimpat
70
What class of drug is Lacosamide
C-V
71
Lacosamide warnings
Prolongs PR interval and increases risk of arrhythmias
72
Oxcarbazepine brand name
Trileptal
73
Oxcarbazepine warnings
Increased risk of serious skin reactions: consider screening patients of Asian descent for HLA-B*1502 prior to initiating therapy
Hyponatremia
74
Oxcarbazepine monitoring
Serum Na levels
75
Phenobarbital therapeutic range for adults
20-40 mcg/mL
76
Phenobarbital warnings
Habit forming, respiratory depression, fetal harm
77
Phenobarbital side effects
Physiological dependence, tolerance, hangover effect
78
Phenobarbital (and primidone) is a strong ____ of most enzymes
inducer
79
Phenytoin brand name
Dilantin, Dilantin Infatabs
80
Fosphenytoin brand name
Cerebyx
81
Phenytoin IV:PO ratio
1:1
82
Phenytoin therapeutic range (total level and free level)
total level: 10-20 mcg/mL
| free level: 1-2.5
83
Phenytoin IV administration rate should not exceed ___ mg/min & fosphenytoin IV should not exceed ___ mg PE/min. If given faster than these rates ____ and ____ can occur
Phenytoin - 50 mg/min
fosphenytoin - 150 mg/min
hypotension and cardiac arrhythmias
84
Phenytoin can cause extravasation, which leads to _____
Purple glove syndrome, characterized by edema, pain and bluish discoloration of the skin which can sometimes lead to tissue necrosis
85
Phenytoin should be avoided in patients with a positive ____
HLA-B*1502
| Can also cause fetal harm
86
Phenytoin dose-related (toxicity) side effects
Nystagmus, ataxia, diplopia/blurred vision
87
Phenytoin chronic side effects
Gingival hyperplasia, hair growth, hepatotoxicity
88
Phenytoin monitoring
Serum phenytoin concentration, LFTs
| IV: continuous cardiac and respiratory monitoring
89
Phenytoin and fosphenytoin are strong ____ of several enzymes
inducers
90
Phenytoin and fosphenytoin both have high ____
protein binding & can displace other highly protein-bound drugs or be displaced by other highly protein-bound drugs, causing an increase in levels that can lead to toxicity
91
Between Phenytoin and fosphenytoin, which has lower risk of purple glove syndrome
fosphenytoin
92
Between Phenytoin and fosphenytoin, which one requires a filter
Phenytoin
| remember GAL PLAT
93
Phenytoin must be diluted in ___, is stable for ___ hours, and should not be ____
NS
4 hours
refrigerated
94
Tube feeds (increase/decrease) phenytoin absorption
decrease
| Hold feedings 1-2 hours before and after administration
95
Ethosuximide warnings
Serious skin rash (SJS/TEN), blood dyscrasias
96
Felbamate boxed warnings
Hepatic failure, aplastic anemia
97
Gabapentin brand name
Neurontin
98
Pregabalin brand name
Lyrica
99
Pregabalin drug schedule
C-V
100
What is the prodrug of phenobarbital
Primidone
101
Vigabatrin boxed warning
Causes permanent vision loss
102
Zonisamide contraindication
Hypersensitivity to sulfonamides
103
Zonisamide side effects
Similar to topiramate, including oligohidrosis/hypertheramia and risk of nephrolithiasis
104
All AEDs cause:
CNS depression (e.g, dizziness, confusion, sedation, and ataxia/coordination difficulties)
105
Which AEDs are enzyme inducers
```
Carbamazepine
Oxcarbazepine
Phenytoin
Fosphenytoin
Phenobarbital
Primidone
```
106
Which AED(s) are enzyme inhibitors
Valproic acid (increases lamotrigine levels)
107
All AEDs have a warning for:
Suicide risk and require monitoring of mood
108
Which AED has the highest teratogenic risk
Valproic acid
109
The levels of all AEDs (increase/decrease) during pregnancy and may require a dose (increase/decrease)
Decrease
| Increase
110
Which two AEDs can cause reduced or lack of sweating in young children
Topiramate and zonisamide
111
Which AEDs come in formulations that are easy to swallow for children
Lamotrigine (ODT, chewable tablets)
| Levetiracetam (ODT, oral solution)
112
A child who remains seizure free for _____ can often be tapered off AEDs
1-2 years
113
Formula to adjust phenytoin dose
phenytoin correction = total phenytoin measured/ (0.2 x albumin) + 0.1
114
Ethosuxamide brand name
Zarontin
