A seizure occurs when

excitatory neurons produce a sudden urge of electrical activity in the brain

Seizures can be caused by

temporary conditions such as fever (common in children), infection, alcohol withdrawal, hypoglycemia or electrolyte abnormalities

What does it mean when it says a medication "can lower the seizure threshold"

meaning it can make a person more susceptible to a seizure (these meds should be avoided in people with a history of seizures)

What is epilepsy

a chronic seizure disorder

Most common test used to diagnose epilepsy, records electrical activity in the brain

electroencephalogram (EEG)

(can show abnormal patterns even when the patient is not having a seizure)

Drugs that can lower the seizure threshold

bupropion, clozapine, theophylline, varenicline, carbapenems, lithium, meperidine, penicillins, quinolones, tramadol, acyclovir, valacyclovir, cephalosporins

Define focal seizures

start on one side of the brain but can spread to the other side

(further classified)

Define generalized seizures

start on both sides of the brain

Define focal aware seizure

no loss of consciousness

Define focal seizure with impaired awareness

the patient experiences loss of consciousness

Define clonic symptoms

sustained rhythmical jerking movements

Define atonic symptoms

limp or weak muscles

Define myoclonus symptoms

muscle twitching

Define tonic symptoms

rigid or tense muscles

Generalized seizures with non-motor symptoms are called

absence seizures (typically start as staring spells)

Define status epilepticus (SE)

a seizure that lasts 5 mins or more

SE treatment phases

stabilization phase --> initial treatment phase --> second treatment phase

What medications are given in the initial treatment phase of SE (5-20 mins)

IV lorazepam or IM midazolam

alternatives: rectal diazepam (Diastat), intranasal or buccal midazolam

What medications are given in the second treatment phase of SE (20- 40 mins)

IV fosphenytoin, valproic acid, levetiracetam

(phenobarbital if others are unavailable)

Non-drug and alternative options for chronic seizure treatment

medical marijuana, ketogenic diet, vagal nerve stimulation or surgical intervention

What is the name of a FDA approved smart watch that monitors seizures in adults and children 6 years of age and older

Embrace2

cannabis-derived medications approved by the FDA to treat rare forms of epilepsy

Cannabidiol or CBD (Epidiolex)

What is a ketogenic diet

high fats, normal protein and low carbohydrates (4:1 ratio of fats to combined protein and carbohydrates)

MOA of BZDs and valproic acid

increase GABA

MOA of phenobarbital

enhance/potentiate GABA effect

MOA of levetiracetam

Ca channel blocker and increase GABA

MOA of ethosuximide

T-type Ca channel blocker

MOA of pregabalin and gabapentin

Ca channel blocker

MOA of oxcarbazepine

Na and Ca channel blocker

MOA of carbamazepine, lamotrigine, phenytoin/fosphenytoin, topiramate

Na channel blockers

Brand name of lamotrigine

Lamictal

If lamotrigine is discontinued for ≥ 5 half-lives (> 6 days for most patients), what should happen?

the initial dose titration must be restarted

Side effects of lamotrigine

alopecia, rash (SJS/TEN), blurred vision, ataxia

If the lamotrigine starter kit is orange, what dose is it?

standard starting dose

If the lamotrigine starter kit is blue, what dose is it?

lower starting dose

If the lamotrigine starter kit is green, what does is it?

higher starting dose

Brand name for levetiracetam

Keppra

IV:PO ratio levetiracetam

1:1

Brand name for topiramate

Topamax

Brand name for topiramate ER

Trokendi XR

Topiramate can decrease the INR in patients on

warfarin

(can also decrease hormonal contraception)

Side effects of topiramate

difficulty with memory, concentration, attention, weight loss, anorexia

Brand name for divalproex

Depakote

Therapeutic range for divalproex

50-100 mcg/mL

Depakote is also used for

bipolar disorder and migraine prophylaxis

Divalproex is a derivative of what

valproic acid

Side effects of valproic acid/divalproex

hyperammonemia, thrombocytopenia, alopecia

Brand name of lacosamide

Vimpat

(it is a C-V)

Brand name of carbamazepine

Tegretol

Therapeutic range for carbamazepine

4-12 mcg/mL

What medication is an autoinducer and will decrease its own levels

carbamazepine

When using carbamazepine, oxcarbazepine and phenytoin in patients of Asian descent, what should they be tested for

HLA-B*1502 allele

Brand name of oxcarbazepine

Trileptal

Side effects of carbamazepine

SIADH, DRESS reactions, hypothyroidism

Brand name for phenytoin

Dilantin

Therapeutic range for phenytoin (total level)

10-20 mcg/mL

Therapeutic range for phenytoin (free level)

1-2.5 mcg/mL

Phenytoin IV administration rate should not exceed

50 mg/min

Fosphenytoin IV rate should not exceed

150 mg PE/min or 2 mg PE/kg/min

Warnings for phenytoin/fosphenytoin

extravasation (leading to purple glove syndrome), DRESS

Side effects of phenytoin dose-related toxicity

nystagmus, ataxia, diplopia,/blurred vision, slurred speech, dizziness, somnolence, lethargy, confusion

prodrug of phenytoin

fosphenytoin

chronic side effects of phenytoin

gingival hyperplasia, hair growth, hepatotoxicity, morbilliform rash (measles-like), increased BG, peripheral neuropathy

Brand name of fosphenytoin

Cerebyx

Brand name of phenobarbital

Sezaby

(C-IV)

Therapeutic range of phenobarbital (adults)

20- 40 mcg

Therapeutic range of phenobarbital (children)

15- 40 mcg/mL

What is the prodrug of phenobarbital

Primidone

Brand name of cenobamate

Xcopri

(C-V)

What is a contraindication for zonisamide

hypersensitivity to sulfonamides

Brand name for zonisamide

Zonegran

the metabolism of phenytoin can become saturated when

there are no enzymes left to metabolize the drug, a small increase in the dose can lead to a large increase in the drug concentration

What kinetics does phenytoin have

michaelis-menten kinetics (also called saturable kinetics)

When should you adjust the total level of phenytoin

when albumin is < 3.5 g/dL and CrCl ≥ 10 mL/min

phenytoin correction calculation

total phenytoin measured/ (0.2 x albumin) + 0.1

AEDS can cause bone loss and

increase fracture risk

(all patients on AEDS should be on calcium and vitamin D)

Women of childbearing age on AEDs should receive

daily folate supplementation

What doses does diastat come in

2.5, 10 and 20 mg

Brand name of oxcarbazepine ER

Oxtellar

How to take Oxtellar ER

on an empty stomach at least one hour before or two hours after food