New Onset Seizure¶

VERSION: 1.2 CREATED: January 13, 2026 REVISED: January 20, 2026 STATUS: Draft - Pending Review

DIAGNOSIS: New Onset Seizure

ICD-10: R56.9 (Unspecified convulsions), G40.909 (Epilepsy, unspecified, not intractable, without status epilepticus)

SCOPE: Initial evaluation and management of first-time unprovoked seizure or first presentation of seizure activity in adults. Covers immediate stabilization, diagnostic workup to identify etiology, acute treatment, and framework for anti-seizure medication (ASM) initiation. Excludes status epilepticus (see "Status Epilepticus" template), pediatric seizures, febrile seizures, and known epilepsy with breakthrough seizures.

PRIORITY KEY: STAT = Immediate | URGENT = Within hours | ROUTINE = Standard | EXT = Extended/atypical cases | — = Not applicable to this setting

SECTION A: ACTION ITEMS¶

1. LABORATORY WORKUP¶

1A. Essential/Core Labs¶

Test	Rationale	Target Finding	ED	HOSP	OPD	ICU
Point-of-care glucose	Hypoglycemia is immediately reversible cause	>70 mg/dL	STAT	STAT	—	STAT
CBC with differential	Infection screen, baseline before ASMs	Normal	STAT	STAT	ROUTINE	STAT
CMP (BMP + LFTs)	Electrolyte abnormalities (Na, Ca, Mg, glucose), renal/hepatic function for ASM dosing	Normal	STAT	STAT	ROUTINE	STAT
Magnesium	Hypomagnesemia lowers seizure threshold	>1.8 mg/dL	STAT	STAT	ROUTINE	STAT
Calcium (ionized if available)	Hypocalcemia can cause seizures	Normal (ionized 4.5-5.3 mg/dL)	STAT	STAT	ROUTINE	STAT
Urine drug screen	Illicit drugs (cocaine, amphetamines) and withdrawal states	Negative	STAT	STAT	ROUTINE	STAT
Blood alcohol level	Alcohol intoxication or withdrawal	Correlate with history	STAT	STAT	—	STAT
Urinalysis	UTI can provoke seizures (especially elderly)	Negative	STAT	STAT	ROUTINE	STAT
Prolactin level	Elevated if drawn within 10-20 min of event; helps distinguish seizure from non-epileptic event	Elevated 2-3× baseline (if drawn <20 min)	STAT	—	—	STAT
Phosphorus	Hypophosphatemia lowers seizure threshold (especially alcohol withdrawal)	>2.5 mg/dL	STAT	STAT	ROUTINE	STAT
Lactate	Elevated post-ictal confirms recent seizure; metabolic acidosis screen	Mild elevation acceptable post-ictal	STAT	STAT	—	STAT

1B. Extended Workup (Second-line)¶

Test	Rationale	Target Finding	ED	HOSP	OPD	ICU
TSH	Thyroid dysfunction can affect seizure threshold	Normal	URGENT	ROUTINE	ROUTINE	URGENT
Ammonia	Hepatic encephalopathy, urea cycle disorders	Normal (<35 μmol/L)	URGENT	ROUTINE	—	URGENT
Troponin	Cardiac ischemia as cause or consequence	Negative	URGENT	ROUTINE	—	URGENT
ECG	Arrhythmia, prolonged QTc (some ASMs), Brugada	Normal	URGENT	ROUTINE	ROUTINE	URGENT
Blood gas (ABG or VBG)	Acidosis, hypoxia	Normal or mild post-ictal acidosis	URGENT	ROUTINE	—	URGENT
Serum osmolality	Hypo/hyperosmolar states	280-295 mOsm/kg	URGENT	ROUTINE	—	URGENT
Pregnancy test (urine or serum β-hCG)	Eclampsia; affects imaging and ASM choice	Negative (or explains eclampsia if positive)	STAT	STAT	ROUTINE	STAT
B12 level	Deficiency associated with seizures	Normal (>300 pg/mL)	—	ROUTINE	ROUTINE	—
Folate level	Deficiency can lower threshold; important for women of childbearing potential	Normal	—	ROUTINE	ROUTINE	—

1C. Rare/Specialized (Refractory or Atypical)¶

Test	Rationale	Target Finding	ED	HOSP	OPD	ICU
Serum/urine toxicology (expanded panel)	Synthetic drugs, medications not on standard screen	Negative	URGENT	EXT	EXT	URGENT
Heavy metals (lead, mercury)	Occupational exposure, pica	Normal	—	EXT	EXT	—
Ceruloplasmin, serum copper	Wilson disease (young patients)	Normal	—	EXT	EXT	—
HIV	HIV-associated CNS disease	Negative	—	ROUTINE	ROUTINE	—
RPR/VDRL	Neurosyphilis	Negative	—	ROUTINE	ROUTINE	—
Autoimmune encephalitis panel (serum)	Anti-NMDAR, LGI1, CASPR2, GABA-B if clinical suspicion	Negative	—	EXT	EXT	—
Paraneoplastic panel (serum)	Subacute onset, smoking, weight loss	Negative	—	EXT	EXT	—
Porphyrins (urine/serum)	Acute intermittent porphyria	Normal	—	EXT	EXT	—
Genetic epilepsy panel	Young onset, family history, refractory	Variable	—	—	EXT	—

2. DIAGNOSTIC IMAGING & STUDIES¶

2A. Essential/First-line¶

Study	Timing	Target Finding	Contraindications	ED	HOSP	OPD	ICU
CT head without contrast	Immediate in ED	Mass, hemorrhage, stroke, calcification, hydrocephalus	Pregnancy (relative - benefit usually outweighs risk)	STAT	STAT	—	STAT
MRI brain with and without contrast (epilepsy protocol)*	Within 24-48h if inpatient; within 2 weeks if outpatient	Tumor, mesial temporal sclerosis, cortical dysplasia, encephalitis, stroke, vascular malformation	GFR <30, gadolinium allergy, pacemaker	URGENT	URGENT	ROUTINE	URGENT
EEG (routine)	Within 24h if possible; ideally within 24-48h of seizure	Epileptiform discharges (spikes, sharp waves), focal slowing	None significant	URGENT	URGENT	ROUTINE	URGENT

Epilepsy MRI protocol should include: thin-cut coronal T2/FLAIR through hippocampi, 3D T1 volumetric, T2, SWI, DWI, post-contrast T1

IMPORTANT: CT head is useful for acute exclusion of hemorrhage, large mass, or hydrocephalus but is NOT sufficient to identify seizure etiology. MRI brain with epilepsy protocol remains the gold standard and should be obtained in all patients with new onset seizure.

2B. Extended¶

Study	Timing	Target Finding	Contraindications	ED	HOSP	OPD	ICU
Continuous EEG (cEEG) monitoring	If altered mental status persists, suspected non-convulsive status	Non-convulsive seizures, non-convulsive status epilepticus	None significant	—	URGENT	—	URGENT
Prolonged ambulatory EEG (24-72h)	Outpatient if routine EEG non-diagnostic	Capture interictal or ictal activity	None significant	—	—	ROUTINE	—
Video-EEG monitoring	If diagnosis uncertain (vs. psychogenic)	Correlate clinical events with EEG	None significant	—	ROUTINE	ROUTINE	—
MRA/MRV brain	If vascular etiology suspected	AVM, aneurysm, venous thrombosis	Same as MRI	—	ROUTINE	ROUTINE	—
CT angiography head	If MRA unavailable and vascular cause suspected	Vascular malformation, aneurysm	Contrast allergy, renal insufficiency	URGENT	URGENT	—	URGENT
Echocardiogram	If embolic stroke suspected as cause	Thrombus, PFO, vegetation	None significant	—	ROUTINE	ROUTINE	—
Chest X-ray	Aspiration risk post-ictal, lung cancer screening if paraneoplastic suspected	Clear lungs or mass	None significant	URGENT	ROUTINE	—	URGENT

2C. Rare/Specialized¶

Study	Timing	Target Finding	Contraindications	ED	HOSP	OPD	ICU
PET-CT brain (interictal FDG)	Epilepsy surgery workup	Focal hypometabolism	Pregnancy, uncontrolled diabetes	—	EXT	EXT	—
SPECT (ictal/interictal)	Epilepsy surgery workup	Ictal hyperperfusion	Requires seizure capture	—	EXT	EXT	—
MEG (magnetoencephalography)	Epilepsy surgery workup	Localize epileptogenic focus	Metallic implants	—	—	EXT	—
Neuropsychological testing	Pre-surgical evaluation, cognitive concerns	Lateralizing deficits	Patient cooperation	—	—	EXT	—
Wada test (intracarotid amobarbital)	Pre-surgical language/memory lateralization	Language and memory dominance	Contrast allergy, vascular anomaly	—	—	EXT	—

LUMBAR PUNCTURE¶

Indication: Suspected CNS infection (meningitis, encephalitis), autoimmune encephalitis, carcinomatous meningitis, or atypical presentation with fever/immunocompromise

Timing: URGENT if infection suspected; ROUTINE if autoimmune workup

Volume Required: 15-20 mL (standard diagnostic); 20-30 mL if malignancy suspected

Study	Rationale	Target Finding	ED	HOSP	OPD	ICU
Opening pressure	Elevated ICP, mass effect	10-20 cm H2O	URGENT	ROUTINE	ROUTINE	URGENT
Cell count (tubes 1 and 4)	Infection, inflammation	WBC <5; RBC 0	URGENT	ROUTINE	ROUTINE	URGENT
Protein	Elevated in infection, inflammation	15-45 mg/dL	URGENT	ROUTINE	ROUTINE	URGENT
Glucose with serum glucose	Low in bacterial/fungal/TB meningitis	>60% serum	URGENT	ROUTINE	ROUTINE	URGENT
Gram stain and culture	Bacterial meningitis	No organisms	URGENT	ROUTINE	ROUTINE	URGENT
BioFire FilmArray ME Panel	Rapid pathogen identification (14 pathogens)	Negative	URGENT	ROUTINE	—	URGENT
HSV-1/2 PCR	HSV encephalitis (most common treatable cause)	Negative	URGENT	ROUTINE	ROUTINE	URGENT
Autoimmune encephalitis panel (CSF)	If clinical suspicion for autoimmune etiology	Negative	—	ROUTINE	ROUTINE	—
Cytology	Carcinomatous meningitis	Negative	—	ROUTINE	ROUTINE	—
VDRL (CSF)	Neurosyphilis	Negative	—	ROUTINE	ROUTINE	—
Oligoclonal bands	If demyelinating disease suspected	Negative or matched with serum	—	ROUTINE	ROUTINE	—

Special Handling: HSV PCR can be sent on refrigerated sample. Cytology requires rapid transport (<1 hour). Cell count must be processed within 1 hour.

Contraindications: Elevated ICP without imaging (CT first), coagulopathy (INR >1.5, platelets <50K), skin infection at LP site

3. TREATMENT¶

3A. Acute/Emergent¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Lorazepam IV/IM (if actively seizing)	IM	-	0.1 mg/kg :: IV :: once :: 0.1 mg/kg IV (max 4 mg); may repeat once in 5 min	Respiratory depression, severe hypotension	RR, O2 sat, BP; have airway equipment ready	STAT	STAT	—	STAT
Midazolam IM (if no IV access)	IM	-	10 mg :: IM :: - :: 10 mg IM (if >40 kg) or 0.2 mg/kg IM	Respiratory depression	RR, O2 sat; have airway equipment ready	STAT	STAT	—	STAT
Midazolam intranasal (if no IV access)	IV	-	5 mg :: - :: - :: 5 mg per nostril (total 10 mg)	Respiratory depression	RR, O2 sat	STAT	STAT	—	STAT
Dextrose 50% IV	IV	-	25-50 mL :: IV :: - :: 25-50 mL IV if hypoglycemia confirmed or suspected	Hyperglycemia	Glucose	STAT	STAT	—	STAT
Thiamine IV	IV	-	100-500 mg :: IV :: - :: 100-500 mg IV BEFORE glucose if alcohol use suspected	None significant	None	STAT	STAT	—	STAT
Supplemental oxygen	INH	-	2-4 L NC or non-rebreather as needed	None	O2 sat >94%	STAT	STAT	—	STAT
IV fluids (isotonic)	IV	-	NS or LR bolus if hypotensive; maintenance if euvolemic	Fluid overload, severe hyponatremia	I/O, BP, Na	STAT	STAT	—	STAT
Flumazenil (rescue only)	IV	-	0.2 mg :: IV :: - :: 0.2 mg IV over 30 sec; may repeat 0.2 mg q1min to max 1 mg	Chronic benzodiazepine use; seizure history; tricyclic overdose	CAUTION: May lower seizure threshold and precipitate seizures; use only if severe respiratory depression unresponsive to supportive care	STAT	STAT	—	STAT

3B. Anti-Seizure Medications (ASMs) - Acute Loading¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Levetiracetam IV	IV	First-line acute loading	40-60 mg/kg :: IV :: - :: 40-60 mg/kg IV (max 4500 mg) over 15 min; OR 1500-3000 mg IV	None significant; reduce dose if CrCl <50	Somnolence, agitation (rare)	STAT	STAT	—	STAT
Levetiracetam PO	PO	Acute loading if stable	1500-3000 mg :: PO :: - :: 1500-3000 mg PO × 1, then start maintenance	Same	Same	URGENT	URGENT	URGENT	—
Fosphenytoin IV	IV	Alternative first-line	20 mg :: IV :: - :: 20 mg PE/kg IV at 150 mg PE/min (max rate)	AV block, sinus bradycardia, pregnancy (relative)	Continuous cardiac monitoring, BP; purple glove syndrome rare with fosphenytoin	STAT	STAT	—	STAT
Phenytoin IV	IV	If fosphenytoin unavailable	20 mg/kg :: IV :: - :: 20 mg/kg IV at max 50 mg/min	AV block, sinus bradycardia, pregnancy	Cardiac monitor, BP; give via large vein (tissue necrosis risk)	STAT	STAT	—	STAT
Valproate IV	IV	Alternative (broad-spectrum)	40 mg/kg :: IV :: - :: 40 mg/kg IV over 10 min (max 3000 mg)	Pregnancy (teratogenic - neural tube defects), hepatic disease, mitochondrial disease, urea cycle disorders	LFTs, ammonia, platelets; pancreatitis risk	STAT	STAT	—	STAT
Lacosamide IV	IV	Alternative first-line	200-400 mg :: IV :: - :: 200-400 mg IV over 15-30 min	PR prolongation >200 ms, 2nd/3rd degree AV block	ECG for PR interval; dizziness	URGENT	URGENT	—	URGENT

3C. Anti-Seizure Medications (ASMs) - Maintenance Therapy¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Levetiracetam	IV	First-line maintenance	500-1500 mg :: IV :: BID :: 500-1500 mg PO/IV BID; start 500 mg BID, may increase by 500 mg/dose weekly; max 3000 mg/day	Renal impairment (adjust per CrCl)	Behavioral changes (irritability, depression - "Keppra rage"); renal function	—	ROUTINE	ROUTINE	ROUTINE
Lamotrigine	-	First-line (especially women of childbearing potential)	25 mg :: PO :: daily :: Start 25 mg daily × 2 weeks; then 50 mg daily × 2 weeks; then 100 mg daily; target 200-400 mg/day in divided doses	Slow titration required (SJS/TEN risk)	Rash (stop if any rash; SJS/TEN risk higher with fast titration or valproate co-therapy)	—	ROUTINE	ROUTINE	—
Lacosamide	PO	First-line alternative	100 mg :: PO :: BID :: Start 100 mg PO BID; increase by 100 mg/day weekly; target 200-400 mg BID; max 400 mg BID	PR prolongation, 2nd/3rd degree AV block, severe hepatic impairment	ECG at baseline and dose changes; dizziness, diplopia	—	ROUTINE	ROUTINE	ROUTINE
Oxcarbazepine	PO	Focal seizures	300 mg :: PO :: BID :: Start 300 mg PO BID; increase by 300-600 mg/day every week; target 1200-2400 mg/day in divided doses	Hypersensitivity to carbamazepine	Sodium (hyponatremia in 2-3%); HLA-B*1502 screening in at-risk populations	—	ROUTINE	ROUTINE	—
Carbamazepine	PO	Focal seizures	200 mg :: PO :: BID :: Start 200 mg PO BID; increase by 200 mg/day weekly; target 800-1200 mg/day; max 1600 mg/day	AV block; bone marrow suppression; concurrent MAOIs	CBC, LFTs, sodium at baseline and periodically; HLA-B*1502 screening	—	ROUTINE	ROUTINE	—
Valproate/Divalproex	PO	Generalized seizures	10-15 mg/kg :: PO :: - :: Start 10-15 mg/kg/day in divided doses; increase by 5-10 mg/kg/week; target 1000-2000 mg/day; max 60 mg/kg/day	Pregnancy (teratogenic); hepatic disease; mitochondrial disease; pancreatitis history	LFTs, ammonia, CBC, platelets at baseline, then q3-6mo; weight gain, hair loss, tremor	—	ROUTINE	ROUTINE	ROUTINE
Phenytoin	PO	Focal or generalized	300-400 mg :: PO :: daily :: 300-400 mg daily (extended release) or divided TID (immediate release); adjust by level	Pregnancy (relative - fetal hydantoin syndrome); AV block	Free phenytoin level (target 1-2 μg/mL); total level 10-20 μg/mL; CBC, LFTs; gingival hyperplasia, hirsutism	—	ROUTINE	ROUTINE	ROUTINE
Brivaracetam	PO	Alternative to levetiracetam	50 mg :: PO :: BID :: Start 50 mg PO BID; may increase to 100 mg BID; max 200 mg/day	Hepatic impairment (reduce dose)	Less behavioral side effects than levetiracetam; somnolence; Schedule C-V	—	ROUTINE	ROUTINE	ROUTINE
Zonisamide	PO	Adjunctive or monotherapy	100 mg :: PO :: daily :: Start 100 mg daily; increase by 100 mg every 2 weeks; target 300-400 mg daily; max 600 mg/day	Sulfonamide allergy; kidney stones	Kidney stones (carbonic anhydrase inhibitor); oligohidrosis (pediatric); metabolic acidosis	—	—	ROUTINE	—
Topiramate	PO	Adjunctive or monotherapy	25 mg :: PO :: BID :: Start 25 mg BID; increase by 50 mg/day weekly; target 200-400 mg/day in divided doses; max 400 mg/day	Kidney stones; metabolic acidosis; glaucoma	Cognitive impairment ("dopamax"); paresthesias; kidney stones; weight loss	—	—	ROUTINE	—
Clobazam	PO	Adjunctive therapy	5-10 mg :: PO :: daily :: Start 5-10 mg daily; increase by 5-10 mg weekly; max 40 mg/day in divided doses	Severe hepatic impairment; sleep apnea (untreated)	Sedation; tolerance may develop; CYP2C19 poor metabolizers need lower dose	—	ROUTINE	ROUTINE	—
Perampanel	PO	Adjunctive for focal or GTCS	2 mg :: PO :: qHS :: Start 2 mg qHS; increase by 2 mg weekly; target 8-12 mg qHS; max 12 mg/day	None absolute	Psychiatric effects (aggression, hostility); dizziness; take at bedtime; Schedule III	—	—	ROUTINE	—
Cenobamate	PO	Adjunctive for focal	12.5 mg :: PO :: daily :: Start 12.5 mg daily × 2 weeks; titrate slowly per package insert; target 200-400 mg daily	Familial short QT syndrome	Very slow titration required (DRESS risk); QT shortening; titration pack available	—	—	ROUTINE	—
Phenobarbital	IV	Refractory or resource-limited	15-20 mg/kg :: IV :: - :: Load 15-20 mg/kg IV; maintenance 1-3 mg/kg/day (60-180 mg/day); target level 15-40 μg/mL	Porphyria; severe respiratory disease	Sedation; cognitive effects; drug interactions (CYP inducer); level monitoring	—	ROUTINE	ROUTINE	ROUTINE

3D. Symptomatic Treatments¶

Treatment	Route	Indication	Dosing	Pre-Treatment Requirements	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Acetaminophen	IV	Post-ictal headache	650-1000 mg :: IV :: q6h :: 650-1000 mg PO/IV q6h PRN; max 3000 mg/day (2000 mg if liver disease)	-	Severe hepatic impairment	LFTs if chronic use	URGENT	ROUTINE	ROUTINE	URGENT
Ibuprofen	PO	Post-ictal headache	400-600 mg :: PO :: PRN :: 400-600 mg PO q6-8h PRN; max 2400 mg/day	-	Renal impairment; GI bleed; post-CABG	Renal function if prolonged use	—	ROUTINE	ROUTINE	—
Ondansetron	IV	Post-ictal nausea	4-8 mg :: IV :: q8h :: 4-8 mg IV/PO q8h PRN	-	QT prolongation; severe hepatic impairment	QTc if multiple doses	URGENT	ROUTINE	ROUTINE	URGENT
Lorazepam	IV	Post-ictal agitation (if severe)	0.5-2 mg :: IV :: PRN :: 0.5-2 mg IV/PO PRN; use with caution	-	Respiratory depression; altered mental status	RR, sedation level; avoid if post-ictal confusion resolving	URGENT	URGENT	—	URGENT
Sertraline	PO	Depression/anxiety (chronic)	50 mg :: PO :: daily :: Start 50 mg daily; increase by 25-50 mg q1-2 weeks; max 200 mg daily	-	Concurrent MAOIs	Suicidality monitoring weeks 1-4	—	—	ROUTINE	—
Escitalopram	PO	Depression/anxiety (chronic)	10 mg :: PO :: daily :: Start 10 mg daily; max 20 mg daily	-	Concurrent MAOIs; QT prolongation	QTc if risk factors	—	—	ROUTINE	—
Melatonin	PO	Sleep disturbance	3-5 mg :: PO :: qHS :: 3-5 mg PO qHS	-	None significant	Well tolerated; may help with ASM-related sleep disruption	—	ROUTINE	ROUTINE	—
Trazodone	PO	Insomnia	25-100 mg :: PO :: qHS :: 25-100 mg PO qHS	-	Concurrent MAOIs	Orthostatic hypotension; priapism (rare)	—	ROUTINE	ROUTINE	—

3E. Second-line/Refractory¶

Treatment	Route	Indication	Dosing	Contraindications	Monitoring	ED	HOSP	OPD	ICU
Add second ASM	-	-	Choose complementary mechanism; see maintenance options	Per specific agent	Per specific agent	—	ROUTINE	ROUTINE	ROUTINE
Epilepsy surgery evaluation referral	-	-	For drug-resistant epilepsy (failed 2+ appropriately chosen ASMs)	N/A	N/A	—	EXT	EXT	—
Vagus nerve stimulator (VNS)	-	-	For drug-resistant epilepsy not surgical candidates	N/A	Device checks	—	—	EXT	—
Dietary therapy (ketogenic diet, modified Atkins)	-	-	For drug-resistant epilepsy	Fatty acid oxidation disorders; pyruvate carboxylase deficiency	Metabolic panels; lipids; kidney function	—	—	EXT	—

4. OTHER RECOMMENDATIONS¶

4A. Referrals & Consults¶

Recommendation	Indication	ED	HOSP	OPD	ICU
Neurology consult	All new onset seizures for evaluation and management	URGENT	URGENT	ROUTINE	URGENT
Epilepsy specialist referral	Diagnostic uncertainty, refractory seizures, surgical candidacy	—	ROUTINE	ROUTINE	—
EEG technologist/neurodiagnostics	EEG scheduling; continuous EEG if indicated	URGENT	URGENT	ROUTINE	URGENT
Neurosurgery consult	Structural lesion requiring intervention (tumor, AVM, SDH)	—	URGENT	EXT	URGENT
Medical toxicology consult	Suspected drug/toxin-induced seizure	URGENT	ROUTINE	—	URGENT
Infectious disease consult	CNS infection confirmed or suspected	—	URGENT	—	URGENT
Oncology consult	Brain tumor identified	—	ROUTINE	ROUTINE	—
Psychiatry consult	Depression, anxiety post-diagnosis; psychogenic non-epileptic spells suspected	—	ROUTINE	ROUTINE	—
Social work consult	Driving restrictions impact, employment concerns, insurance navigation	—	ROUTINE	ROUTINE	—
Occupational therapy	Work safety evaluation, activity modification	—	ROUTINE	ROUTINE	—
Physical therapy	If post-ictal weakness, falls, injury from seizure	—	ROUTINE	ROUTINE	—
Neuropsychology referral	Cognitive complaints, pre-surgical evaluation	—	—	ROUTINE	—
Women's health/OB-GYN	Contraception counseling (ASM interactions), pregnancy planning	—	—	ROUTINE	—
Epilepsy monitoring unit (EMU) admission	Characterize seizure type, video-EEG monitoring, pre-surgical evaluation	—	EXT	EXT	—
Driving evaluation/rehabilitation	Return to driving assessment when eligible	—	—	EXT	—

4B. Patient Instructions¶

Note: ICU patients typically receive these instructions at step-down or discharge.

Recommendation	ED	HOSP	OPD	ICU
Return to ED immediately if: recurrent seizure, prolonged seizure >5 minutes, head injury, persistent confusion, difficulty breathing, or status epilepticus	✓	✓	✓	—
Do NOT drive until cleared by neurology (driving restrictions per state guidelines; typically require seizure-free interval)	✓	✓	✓	—
Avoid operating heavy machinery, working at heights, or swimming alone	✓	✓	✓	—
Do not bathe alone; showers preferred over baths; keep bathroom door unlocked	✓	✓	✓	—
Inform employer if job involves safety-sensitive duties	—	✓	✓	—
Take ASM exactly as prescribed; do NOT stop abruptly (risk of breakthrough seizures or status epilepticus)	✓	✓	✓	—
Avoid common seizure triggers: sleep deprivation, alcohol, illicit drugs, missed medications	✓	✓	✓	—
Keep a seizure diary: date, time, duration, description, triggers, post-ictal symptoms	—	✓	✓	—
Wear medical identification (bracelet or necklace)	—	✓	✓	—
Educate family/coworkers on seizure first aid: stay with person, protect head, do NOT put anything in mouth, time the seizure, call 911 if >5 minutes	✓	✓	✓	—
Follow up with neurology within 1-2 weeks of discharge	✓	✓	—	—
Bring list of all medications (including OTC and supplements) to all appointments - many interact with ASMs	—	✓	✓	—
Women: discuss contraception with provider; some ASMs reduce efficacy of hormonal contraception	—	✓	✓	—
Report side effects (mood changes, rash, dizziness, cognitive issues) promptly; do NOT stop medication without calling	—	✓	✓	—
Avoid flashing/strobe lights if photosensitive seizures suspected	—	✓	✓	—

4C. Lifestyle & Prevention¶

Note: ICU patients typically receive these recommendations at step-down or discharge.

Recommendation	ED	HOSP	OPD	ICU
Sleep hygiene: aim for 7-9 hours nightly; maintain regular sleep schedule	—	✓	✓	—
Avoid alcohol (lowers seizure threshold; interacts with ASMs)	✓	✓	✓	—
Avoid illicit drugs (especially stimulants: cocaine, amphetamines)	✓	✓	✓	—
Stress management techniques	—	—	✓	—
Regular moderate exercise (not extreme sleep deprivation from overtraining)	—	—	✓	—
Medication adherence: use pill organizers, phone alarms, refill reminders	—	✓	✓	—
Folic acid supplementation 1-4 mg daily for women of childbearing potential (especially if on enzyme-inducing ASMs)	—	✓	✓	—
Bone health: vitamin D 1000-2000 IU daily; calcium as needed (enzyme-inducing ASMs affect bone density)	—	—	✓	—
Avoid known personal triggers (flashing lights, certain foods, stress, if identified)	—	✓	✓	—
Home safety modifications: pad sharp furniture corners, avoid glass shower doors, use microwave instead of stovetop when alone	—	✓	✓	—
Seizure alert devices or apps for those living alone (optional)	—	—	✓	—
Smoking cessation (increases ASM metabolism; general health)	—	✓	✓	—

SECTION B: REFERENCE (Expand as Needed)¶

5. DIFFERENTIAL DIAGNOSIS¶

Alternative Diagnosis	Key Distinguishing Features	Tests to Differentiate
Syncope (convulsive syncope)	Brief (<15 sec), triggered by standing/Valsalva/micturition, rapid recovery, no post-ictal confusion, possible prodrome (lightheaded, tunnel vision)	ECG, orthostatic vitals, tilt table test, echocardiogram
Psychogenic non-epileptic spells (PNES)	Variable/atypical semiology, prolonged duration, preserved awareness with bilateral movements, eye closure, pelvic thrusting, no post-ictal confusion, psychiatric comorbidity	Video-EEG capturing event; normal prolactin
Transient ischemic attack (TIA)	Negative symptoms (weakness, numbness), no LOC, no convulsive activity	MRI DWI, vascular imaging
Migraine with aura	Gradual onset, spreading symptoms, headache follows, stereotyped	Clinical history, normal EEG
Hypoglycemia	Diaphoresis, tremor, confusion, rapid glucose corrects symptoms	Fingerstick glucose
Cardiac arrhythmia	Palpitations, sudden LOC without warning, rapid recovery	ECG, Holter monitor, event recorder, EP study
Transient global amnesia	Isolated anterograde amnesia, repetitive questioning, no convulsive activity	Clinical presentation (self-limited), MRI DWI (hippocampal)
Sleep disorders (parasomnias, cataplexy)	Occur from sleep, specific features (cataplexy with emotion)	Sleep study, clinical history
Movement disorders (dystonia, tics)	Stereotyped, no LOC, suppressible (tics), may have sensory urge	Clinical history, video
Drug intoxication/withdrawal	History of substance use, known withdrawal timeline	Toxicology screen, history
Metabolic encephalopathy	Gradual onset, diffuse abnormality, asterixis, no discrete seizures	Labs (ammonia, glucose, Na), EEG (diffuse slowing)

6. MONITORING PARAMETERS¶

Parameter	Frequency	Target/Threshold	Action if Abnormal	ED	HOSP	OPD	ICU
Neurologic exam (level of consciousness, focal deficits)	Q1-2h in ED; Q4h inpatient; each visit OPD	Return to baseline	If prolonged post-ictal state: continuous EEG to rule out non-convulsive status	✓	✓	✓	✓
Vital signs	Continuous in ED/ICU; Q4h floor	Stable	Treat hyperthermia, hypotension, hypoxia	✓	✓	—	✓
Respiratory monitoring (post-benzodiazepine)	RR q15min × 1h post-administration; SpO2 continuous	RR ≥12; SpO2 ≥94%	Supplemental O2; airway management; consider flumazenil only if severe	✓	✓	—	✓
Glucose	On arrival; repeat if altered	>70 mg/dL	Dextrose if low	✓	✓	—	✓
Electrolytes (Na, Ca, Mg)	On arrival; daily if abnormal	Normal ranges	Correct deficiencies; identify cause	✓	✓	✓	✓
ASM level (phenytoin, valproate, phenobarbital, carbamazepine)	Trough level 5-7 days after initiation or dose change; PRN	Therapeutic range (drug-specific)	Adjust dose; check free level for phenytoin	—	✓	✓	✓
LFTs	Baseline; q3-6 months on valproate, carbamazepine	Normal	Discontinue if hepatotoxicity; hold if transaminases >3× ULN	—	✓	✓	✓
CBC	Baseline; q3-6 months on carbamazepine, valproate	Normal	Discontinue if significant bone marrow suppression	—	✓	✓	✓
Sodium	Baseline; periodically on oxcarbazepine, carbamazepine	>130 mEq/L	Reduce dose or switch if severe hyponatremia	—	✓	✓	✓
EEG	Within 24-48h of first seizure; repeat if diagnosis unclear	No ongoing seizures	Adjust treatment if epileptiform activity or non-convulsive seizures	✓	✓	✓	✓
MRI brain	Within 2 weeks of first seizure; sooner if structural cause suspected	No new lesions	Address structural cause; refer to appropriate specialist	—	✓	✓	—

ASM Therapeutic Level Reference:

ASM	Therapeutic Range	Notes
Phenytoin (total)	10-20 μg/mL	Check FREE level (1-2 μg/mL) if hypoalbuminemia, renal failure, or pregnancy
Valproate	50-100 μg/mL	Higher levels may be needed; monitor for toxicity
Carbamazepine	4-12 μg/mL	Autoinduction occurs over 2-4 weeks
Phenobarbital	15-40 μg/mL	Sedation common at higher levels
Lacosamide	10-20 μg/mL	Level monitoring not routinely required
Levetiracetam	12-46 μg/mL	Level monitoring not routinely required; clinical response guides dosing

7. DISPOSITION CRITERIA¶

Disposition	Criteria
Discharge home	Single, self-limited seizure; returned to baseline; no dangerous etiology identified on initial workup; reliable adult supervision for 24h; ASM initiated or deferred with close follow-up; outpatient EEG and MRI arranged; understands return precautions and driving restriction
Admit to floor (observation)	Prolonged post-ictal period; multiple seizures; new structural lesion requiring monitoring; ASM loading requiring observation; social situation preventing safe discharge; need for inpatient EEG; new focal neurologic deficit
Admit to ICU	Status epilepticus (current or recent); recurrent seizures despite treatment; need for continuous EEG monitoring; airway compromise; hemodynamic instability; significant aspiration; large structural lesion with mass effect; CNS infection
Transfer to higher level	MRI unavailable; EEG unavailable; neurology not available for consultation; need for neurosurgical intervention unavailable at facility

8. EVIDENCE & REFERENCES¶

Recommendation	Evidence Level	Source
ILAE 2017 seizure classification	Class I	Fisher RS et al. Epilepsia 2017
ILAE 2014 practical definition of epilepsy	Class I	Fisher RS et al. Epilepsia 2014
EEG within 24-48h increases yield	Class II, Level B	AAN Practice Parameter 2007
MRI superior to CT for epilepsy evaluation	Class I, Level A	ILAE Commission Report 2019
Levetiracetam non-inferior to phenytoin for acute seizure cessation	Class I, Level A	ESETT Trial, NEJM 2019
Risk of recurrence after first unprovoked seizure ~40-50%	Class I	Hauser et al., NEJM 1998
Starting ASM after first seizure reduces recurrence but not long-term remission	Class I, Level A	FIRST and MESS trials
Lamotrigine and levetiracetam preferred in women of childbearing potential	Class II, Level B	AAN/AES Guidelines 2009, MONEAD Study
Driving restrictions reduce accident risk	Class II, Level B	Multiple observational studies
Prolactin elevation supports diagnosis of epileptic seizure (if drawn <20 min)	Class II, Level B	Chen et al., Neurology 2005
Continuous EEG detects non-convulsive status in altered patients	Class II, Level B	Claassen et al., Neurology 2004
Folate supplementation reduces teratogenicity risk	Class II, Level B	AAN Practice Parameter

CHANGE LOG¶

v1.2 (January 20, 2026) - Added lactate to Section 1A core labs (elevated post-ictal confirms recent seizure) per R4 - Added respiratory monitoring parameters to Section 6 (RR, SpO2 post-benzodiazepine) per R2 - Added Schedule C-V controlled substance note to brivaracetam in Section 3C per R3 - Added ICU column to Sections 4B and 4C for format consistency per R1 - Added explanatory notes for ICU exclusion in patient instructions/lifestyle sections

v1.1 (January 13, 2026) - Updated levetiracetam loading dose to range (40-60 mg/kg) per physician preference - Added phosphorus to core labs (hypophosphatemia in alcohol withdrawal) - Added flumazenil to acute treatments with seizure threshold caution - Added note that CT insufficient for etiology; MRI is gold standard - Updated driving restriction language to generic "per state guidelines" - Added ASM therapeutic level reference table to Section 6 - Added ILAE 2017 seizure classification and 2014 epilepsy definition to references

v1.0 (January 13, 2026) - Initial creation - Comprehensive ASM section with individual drug rows and complete dosing - Included 14 maintenance ASMs with titration schedules - Added acute loading options (levetiracetam, fosphenytoin, valproate, lacosamide) - LP section for infectious/autoimmune workup - Extensive differential diagnosis including syncope, PNES, cardiac causes - Complete patient instructions including driving, safety, seizure first aid - Setting-appropriate coverage across ED, HOSP, OPD, ICU