Use this as the emergency entry point: stabilize, give benzodiazepine therapy early, load a second-line ASM, and escalate to anesthetic infusion if seizures persist beyond 30 minutes.
Courtesy of Dr. Gena Ghearing
| Phase | Time Range | Intervention & Dosing |
|---|---|---|
| Stabilization Phase | 1–5 minutes |
|
| Initial Therapy Phase | 5–10 minutes |
|
| Second-line Therapy | 10–30 minutes |
|
| Refractory Therapy | >30 minutes |
|
| Breakthrough/Recurrence | N/A |
|
| Additional Therapies | N/A |
|
Below is a rapid-reference list of anti-seizure medications (ASMs) with abbreviated adult epilepsy dosing, common adverse effects, and commonly reported laboratory intervals when applicable. Some entries are syndrome-specific, adjunctive, rescue, or off-label uses rather than interchangeable maintenance regimens.
Search within the table or narrow by spectrum and route.
| Medication | Abbreviated Adult Epilepsy Dosing | Common Side Effects | Common Laboratory Reference Range* |
|---|---|---|---|
| Acetazolamide | Oral: 375–1000 mg/day (divided doses) | Paresthesias, fatigue, taste alteration, acidosis, kidney stones | N/A |
| Brivaracetam | Oral or IV: 50–200 mg/day (in 2 divided doses) | Drowsiness, dizziness, fatigue, irritability | N/A |
| Carbamazepine | Oral: 800–1200 mg/day (in 2–4 divided doses; range ~400–1600 mg) | Dizziness, drowsiness, diplopia, ataxia (HLA-B*15:02 screening recommended before initiation for patients with ancestry in populations where HLA-B*15:02 is common; consider HLA-A*31:01 risk according to ancestry and local guidance) | 4–12 µg/mL |
| Cannabidiol (Dravet, LGS, or TSC-associated seizures) | Oral: target 10 mg/kg/day for Dravet/LGS (maximum 20 mg/kg/day); target 25 mg/kg/day for TSC, divided BID | Diarrhea, fatigue, decreased appetite, somnolence | N/A |
| Cenobamate (new) | Oral: 200 mg/day (after gradual titration; max 400 mg/day) | Dizziness, somnolence, fatigue, headache, nausea | No established therapeutic target |
| Clobazam (adjunct for LGS) | Oral: 10–40 mg/day (usually divided BID) | Sedation, drowsiness, drooling | Clobazam 30–300 ng/mL; N-desmethylclobazam 300–3000 ng/mL |
| Clorazepate | Oral: 15–90 mg/day (divided doses) | Drowsiness, dizziness, fatigue, ataxia | N/A |
| Clonazepam (rarely used long-term) | Initial dose should not exceed 1.5 mg/day divided TID; titrate individually. Labeled maximum 20 mg/day. | Sedation, drowsiness, cognitive impairment, tolerance | N/A |
| Diazepam (Oral) | Oral: 4–40 mg/day (divided doses) | Sedation, fatigue, ataxia, muscle weakness | N/A |
| Eslicarbazepine acetate | Oral: 800–1600 mg/day (usually once daily) | Dizziness, headache, diplopia, somnolence | N/A |
| Ethosuximide | Oral: start 500 mg/day and titrate; doses above 1500 mg/day require strict medical supervision (absence seizures) | Nausea, vomiting, lethargy, headache, weight loss | 40–100 µg/mL |
| Everolimus (TSC associated seizures) | Oral: Titrated to trough 5–15 ng/mL | Stomatitis, infections, rash, fatigue | 5–15 ng/mL |
| Felbamate (rarely used – toxicity) | Oral: 1200–3600 mg/day (divided TID–QID) | Sedation, nausea, vomiting, risk of aplastic anemia/liver failure | N/A |
| Fenfluramine | Oral solution: 0.1 mg/kg BID initially; up to 0.35 mg/kg BID (maximum 26 mg/day). Lower maximum with stiripentol plus clobazam. | Decreased appetite, somnolence, diarrhea, fatigue; boxed warning requires echocardiographic monitoring for valvular heart disease and pulmonary arterial hypertension | No established therapeutic target |
| Gabapentin (rarely effective for epilepsy) | Oral: 900–3600 mg/day (divided TID) | Dizziness, somnolence, peripheral edema, ataxia | N/A |
| Ganaxolone (CDKL5 deficiency) | Oral: Titrated to 600 mg TID (1800 mg/day) | Somnolence, pyrexia, salivary hypersecretion | N/A |
| Lacosamide | Oral or IV: 200–400 mg/day divided BID; 600 mg/day was not more effective and caused more adverse reactions in trials | Dizziness, headache, nausea | 10–20 mg/L |
| Lamotrigine | Oral: 100–400 mg/day (in 2 divided doses; slow titration. Note that dosing changes for patients taking drugs that alter metabolism) | Rash (risk of Stevens–Johnson syndrome), dizziness, headache | 3–15 µg/mL |
| Levetiracetam | Oral or IV: 1000–3000 mg/day divided BID; adjust for renal function | Drowsiness, dizziness, irritability, behavioral changes | 10–40 µg/mL |
| Lorazepam | Oral: 2–6 mg/day (divided doses) | Sedation, dizziness, weakness, unsteadiness | N/A |
| Methsuximide | Oral: 300–1200 mg/day | Nausea, vomiting, dizziness, drowsiness | 10–40 µg/mL (as N-desmethylmethsuximide) |
| Midazolam (Nasal) | Nasal: 5 mg per dose (may repeat once) | Nasal discomfort, somnolence, runny nose | N/A |
| Oxcarbazepine | Oral: 600–2400 mg/day (divided BID) | Dizziness, sedation, hyponatremia | 3–35 µg/mL (MHD) |
| Perampanel | Oral: 8–12 mg/day (once daily at bedtime) | Dizziness, somnolence, hostility, irritability, falls | No established therapeutic target |
| Phenobarbital | Oral or IV: 60–200 mg/day (usually once at bedtime) | Sedation, cognitive impairment, ataxia, dependence | 10–40 µg/mL |
| Phenytoin | Oral or IV: 300–400 mg/day (divided BID; ~5–7 mg/kg/day to maintain level 10–20 µg/mL) | Nystagmus, ataxia, gingival hyperplasia, hirsutism, sedation | Total 10–20 µg/mL; free concentration is often more informative with low albumin, renal failure, pregnancy, or interacting drugs |
| Primidone (rarely used) | Oral: 750–1500 mg/day (divided BID–TID) | Sedation, ataxia, nausea, dizziness | N/A |
| Pregabalin (rarely used for epilepsy) | Oral: 150–600 mg/day (divided BID) | Dizziness, somnolence, weight gain, peripheral edema | N/A |
| Rufinamide (rare, LGS) | Oral with food: start 400–800 mg/day divided BID; titrate to a maximum of 3200 mg/day | Dizziness, fatigue, nausea, vomiting | N/A |
| Stiripentol (rare, Dravet) | Oral: 50 mg/kg/day divided BID or TID (maximum 3000 mg/day), used with clobazam for Dravet syndrome in the labeled population | Drowsiness, ataxia, loss of appetite | N/A |
| Tiagabine (rarely used) | Oral: 32–56 mg/day (divided BID–QID) | Dizziness, nervousness, fatigue, tremor | N/A |
| Topiramate | Oral: 100–400 mg/day (divided BID) | Cognitive slowing, weight loss, paresthesias, kidney stones | 5–20 µg/mL |
| Valproate / Divalproex Sodium | Oral (DR/ER) or IV: 1000–3000 mg/day (divided BID–TID; ~15–60 mg/kg/day) | GI upset, tremor, weight gain, hair loss, hepatotoxicity, thrombocytopenia | 50–125 µg/mL |
| Vigabatrin (restricted use; REMS) | For refractory focal seizures: start 1000 mg/day divided BID; titrate to recommended 3000 mg/day | Visual field defects, sedation, irritability | N/A |
| Zonisamide | Oral: 100–400 mg/day (once daily or divided BID) | Dizziness, somnolence, loss of appetite, weight loss | 10–40 mcg/mL |
*Laboratory ranges vary by assay and are not universal treatment targets. Clinical response, toxicity, sample timing, baseline concentration, interactions, protein binding, and free drug levels may matter more than a population interval. Doses are abbreviated educational examples; verify whether each use is labeled, adjunctive, syndrome-specific, or off-label.
Medication table for rapid educational reference only. Verify indication, formulation, interactions, organ-function adjustments, pregnancy considerations, titration, and current prescribing information before use.
These flow charts provide guidance on anti-seizure medication selection based on seizure type, mechanisms of action, and clinical applications:
Context: These 2021 figures are conceptual teaching aids, not current prescribing algorithms. Medication approval, pregnancy guidance, syndrome terminology, and comparative evidence change; verify the current label and guideline for the individual patient.
Monotherapy and add-on therapy options for seizures in adults and children:
Neurobiological targets of commonly used anti-seizure medications:
Treatment approaches for different types of epilepsy in adults and children:
Reference: Löscher, W., Klein, P. The Pharmacology and Clinical Efficacy of Antiseizure Medications: From Bromide Salts to Cenobamate and Beyond. CNS Drugs 35, 935–963 (2021). https://link.springer.com/article/10.1007/s40263-021-00827-8
ASM withdrawal should be performed gradually under medical supervision after careful consideration of seizure recurrence risk factors.
Use the prediction tool below to estimate seizure recurrence risk after medication withdrawal, but always consult your epilepsy specialist before making any medication changes.
| Therapy Category | Description/Details |
|---|---|
| Definition | Drug-resistant epilepsy (DRE) is defined by failure of two tolerated, appropriately chosen and adequately used ASM schedules—whether alone or in combination—to achieve sustained seizure freedom. Referral to a comprehensive epilepsy center should occur promptly so the diagnosis, adherence barriers, epilepsy type, imaging, surgical candidacy, devices, dietary therapy, and psychosocial needs can be reviewed; referral does not commit a patient to surgery. |
| Surgical Options | Resection, lesionectomy, lobar/multilobar resections, or hemispherectomy in catastrophic cases; corpus callosotomy may reduce drop attacks. |
| Neuromodulation Techniques |
VNS: Vagus nerve stimulation (VNS) has demonstrated that approximately 49% of
patients achieve a ≥50% reduction in seizure frequency within 1–2 years (see VNS outcomes).
RNS: Responsive neurostimulation (RNS) offers a median seizure reduction of around 60% over several years (see RNS outcomes). DBS: Deep brain stimulation (DBS) targeting the anterior nucleus of the thalamus has shown a median seizure reduction of about 56% in controlled trials (see DBS outcomes). |
| Dietary & Other Therapies | Ketogenic diet (or variants), immunotherapies, etc. |
| References | ILAE/AAN recommendations; ACNS guidelines; UpToDate; Epilepsy Foundation. |
Most people with epilepsy can have a healthy pregnancy. Management should begin before conception when possible and balance seizure control, the risks of convulsive seizures, and medication-specific fetal risks. Do not stop an antiseizure medication abruptly during pregnancy.
| Risk Level | Medications | Notes |
|---|---|---|
| High Risk | Valproate; also phenobarbital and topiramate when clinically feasible alternatives exist | Valproate has dose-dependent risk for major malformations (neural tube, cardiac) and adverse neurodevelopmental outcomes. The 2024 AAN/AES/SMFM guideline recommends avoiding valproate when clinically feasible; medication changes must still account for seizure type and seizure-control risk. |
| Intermediate | Carbamazepine, Phenytoin | Risk varies by medication and dose. Use the fewest medications and lowest effective doses compatible with seizure control rather than applying a blanket monotherapy rule. |
| Lowest Risk | Lamotrigine, Levetiracetam, Oxcarbazepine | The 2024 guideline recommends considering these when appropriate for the person’s epilepsy to minimize major congenital-malformation risk. No medication is universally safest for every epilepsy. |
Do not use this older table as a current counseling calculator. It reproduces selected results from 2006–2012 publications with different enrollment, comparator, dose, and outcome methods. Current counseling should use the 2024 AAN/AES/SMFM guideline and the latest pregnancy-registry publications. The historical data remain useful for illustrating dose dependence and why estimates differ among registries.
| Medication | NAAPR (Hernandez-Diaz 2012) | UK Register (Morrow 2006) | EURAP (Tomson 2011) |
|---|---|---|---|
| Lamotrigine | 2.0% | 3.2% | 2.0% (<300mg) 4.5% (≥300mg) |
| Levetiracetam | 2.4% | 0% (small sample) | - |
| Carbamazepine | 3.0% | 2.2% | 3.4% (<400mg) 8.7% (≥1000mg) |
| Phenytoin | 2.9% | 3.7% | - |
| Valproate | 9.3% | 6.2% | 5.6% (<700mg) 24.2% (≥1500mg) |
| Topiramate | 4.2% | 7.1% | - |
| Phenobarbital | 5.5% | - | 5.4% (<150mg) 13.7% (≥150mg) |
| Unexposed / Control | 1.1% | 3.5% | - |
Interactions: Carbamazepine, phenytoin, phenobarbital, primidone, and higher-dose topiramate can reduce exposure to some hormonal contraceptives; estrogen-containing contraception can also lower lamotrigine concentrations.
Recommendation: Select contraception with the patient and prescribing clinicians using an interaction checker. IUDs avoid hepatic enzyme-induction interactions; other methods require individualized review.
Current guideline floor: prescribe at least 0.4 mg folic acid daily before conception and during pregnancy for anyone treated with an ASM.
Higher doses: the optimal dose is uncertain. Prior neural-tube defect, nutritional factors, and medication choice warrant individualized maternal-fetal-medicine and neurology guidance rather than an automatic 4 mg rule.
Clearance: Significantly increases for Lamotrigine (>50% drop), Levetiracetam, and Oxcarbazepine.
Action: Establish an individual pre-pregnancy clinical and concentration baseline when useful, then monitor symptoms and levels at a frequency determined by the medication, trimester, seizure risk, and rate of change.
Labor: treat an ongoing convulsive seizure promptly using the institution’s pregnancy-aware acute-seizure protocol while addressing airway, fetal/maternal status, and obstetric causes such as eclampsia.
Postpartum: if doses were increased during pregnancy, make a medication-specific reduction plan before delivery and monitor for toxicity as clearance returns toward baseline. Avoid fixed taper schedules across all ASMs.
Generally safe and encouraged. Infant serum levels are typically low despite presence in milk. Monitor for sedation if on Phenobarbital/Primidone.
Primary guidance: AAN/AES/SMFM practice guideline on teratogenesis, perinatal, and neurodevelopmental outcomes after in-utero ASM exposure (2024). This section supports counseling and does not replace individualized neurology and maternal-fetal-medicine care.