You are in: eMedicine Specialties > Neurology > Seizures and Epilepsy Simple Partial SeizuresArticle Last Updated: Jan 11, 2007AUTHOR AND EDITOR INFORMATIONAuthor: Jane G Boggs, MD, Director of Epilepsy Services and Epilepsy Monitoring, Department of Neurology, Orlando Regional Lucerne Hospital Jane G Boggs is a member of the following medical societies: American Academy of Neurology, American Clinical Neurophysiology Society, American Epilepsy Society, and Stroke Council of the American Heart Association Editors: Joseph F Hulihan, MD, Vice President, Medical Affairs, Ortho-McNeil Janssen Scientific Affairs, LLC; Francisco Talavera, PharmD, PhD, Senior Pharmacy Editor, eMedicine; Selim R Benbadis, MD, Professor, Director of Comprehensive Epilepsy Program, Departments of Neurology and Neurosurgery, University of South Florida School of Medicine, Tampa General Hospital; Matthew J Baker, MD, Consulting Staff, Collier Neurologic Specialists, Naples Community Hospital; Nicholas Y Lorenzo, MD, Chief Editor, eMedicine Neurology; Consulting Staff, Neurology Specialists and Consultants Author and Editor Disclosure Synonyms and related keywords: focal seizures, simple localization-related epilepsy, SPS, epilepsy, simple partial status epilepticus, SPSE, epilepsia partialis continua, Kojewnikoff syndrome, periodic lateralized epileptiform discharges, PLEDs, Landau-Kleffner syndromes, epileptogenic zone, partial seizures, simple partial seizures INTRODUCTIONBackgroundAll partial seizures are characterized by onset in a limited area, or focus, of one cerebral hemisphere. The International Classification of Epileptic Seizures (ICES) classifies simple partial seizures (SPS) as those that are not associated with any impairment of consciousness. Although the ability to respond may be preserved, motor manifestations or anxiety relating to the seizure symptoms may prevent a patient from responding appropriately. The level of consciousness may be difficult to determine during a partial seizure, especially in infants, cognitively impaired individuals, and aphasic patients. The lack of availability of trained persons to interact directly with the patient during and after the seizure can make distinctions between simple and complex partial seizures difficult, even with high-resolution video-EEG. ICES defines an aura as "that portion of the seizure which occurs before consciousness is lost, and for which memory is retained afterwards." Auras without subsequent seizures should be considered a type of SPS. Simple partial status epilepticus (SPSE) includes epilepsia partialis continua (ie, Kojewnikoff syndrome). Some researchers also have included periodic lateralized epileptiform discharges (PLEDs) and the spectrum of Landau-Kleffner syndromes as types of SPSE. PathophysiologyAny structural lesion of the brain that causes an electrical variation in the surrounding tissue can provide an adequate substrate for epileptogenesis. The epileptogenic zone is the area that generates seizures, but it may in fact be clinically silent. The clinical and EEG manifestations may be due to secondary activation of another cortical area.
Interestingly, the areas of the cortex with the lowest threshold for electrical stimulation are those that correspond to the body segments most commonly observed to be the regions responsible for motor or sensory SPS. Penfield and Jasper identified the perioral area, thumb, index finger, and great toe as the areas that usually are affected first in partial seizures. These are all anatomical parts having a disproportionately large area of representation in the cortical homunculus. Psychic SPS are characterized by complex cognitive or affective symptoms, such as déją vu. They more commonly arise in temporal rather than extratemporal regions. Electrical stimulation experiments have demonstrated that similar psychic manifestations can be elicited from noncontiguous locations. This suggests that this type of SPS may have a more diffuse rather than a discrete localization. The origin of autonomic SPS is hypothesized to be hypothalamus, and its clinical manifestations are determined by the pattern of activation of the central autonomic network and the higher order autonomic control areas of the insula and prefrontal cortices. FrequencyUnited StatesAmong all seizures, partial seizures have the highest incidence after the first year of life. The incidence of all partial seizures for subjects aged 1-65 years is approximately 20 cases per 100,000 population. Although observational classification studies are imprecise, an estimated 6-12% of patients with epilepsy have SPS exclusively. The proportions of sensory, motor, special sensory, psychic, and autonomic SPS differ among various population studies, but most agree that SPS are found most frequently in association with other types of seizures. InternationalNot enough studies are available to indicate the incidence of SPS as compared with that in the United States. In general, the incidence of epilepsy and the proportion of partial epilepsy are expected to be higher in developing countries because of the higher rates of infection and overall lower standard of health. Mortality/Morbidity
RaceSPS have no reported predilection for any race or ethnic group. SexMales and females are affected equally. Age
CLINICALHistoryThe ICES lists 18 categories of SPS. All types of SPS can be seen with subsequent complex partial secondarily generalized seizures. The suspicion of SPS is based on the history of typical, reproducible patterns as outlined here.
PhysicalThe physical examination may show subtle or obvious neurological focality.
CausesAny localized structural lesion of the brain can result in SPS, including the following:
DIFFERENTIALSAbsence Seizures Anterior Circulation Stroke Basilar Artery Thrombosis Bell Palsy Benign Childhood Epilepsy Cardioembolic Stroke Cavernous Sinus Syndromes Cerebellar Hemorrhage Chronic Paroxysmal Hemicrania Cluster Headache Complex Partial Seizures Dissection Syndromes Epilepsy, Juvenile Myoclonic Essential Tremor Headache: Pediatric Perspective Hemifacial Spasm Median Neuropathy Meralgia Paresthetica Migraine Headache Migraine Variants Muscle Contraction Tension Headache Persistent Idiopathic Facial Pain
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| Drug Name | Carbamazepine (Tegretol, Tegretol-XR, Carbatrol, Epitol) |
|---|---|
| Description | Tricyclic compound extensively metabolized to active metabolite, CBZ-epoxide. Markedly induces its own metabolism and highly bound to plasma proteins. Available as 100 mg/mL susp; 100 mg chewable tab; 200 mg tab; 100, 200, and 400 mg delayed-release tab (Tegretol-XR); 200, 300 mg extended-release capsules (Carbatrol). |
| Adult Dose | 8-20 mg/kg/d PO bid/qid (all formulations—susp, chewable, or tab) |
| Pediatric Dose | 10-35 mg/kg/d PO bid/qid (all formulations—susp, chewable, or tab) |
| Contraindications | Documented hypersensitivity; concurrent MAOIs |
| Interactions | Decreases estrogen and progestin plasma concentrations with concurrent use of oral contraceptives; also decreases levels of cyclosporin, corticosteroids, protease inhibitors, theophylline, tricyclic antidepressants, antipsychotics, and warfarin May increase danazol levels significantly within 30 days of coadministration (avoid whenever possible); do not coadminister with MAOIs; cimetidine may increase toxicity, especially if taken in first 4 wk of therapy; may decrease primidone and phenobarbital levels—either may increase carbamazepine level; propoxyphene, macrolides may increase carbamazepine levels |
| Pregnancy | D - Unsafe in pregnancy |
| Precautions | Common adverse effects include drowsiness, dizziness, diplopia, ataxia, blurry vision, osteopenia, peripheral neuropathy, hyponatremia, and alopecia Idiosyncratic adverse effects include skin rash, hepatotoxicity, and rarely blood dyscrasias; caution with increased intraocular pressure; obtain CBCs and serum iron baseline prior to treatment, during first 2 months, and yearly or every other year thereafter; caution while driving or performing other tasks requiring alertness |
| Drug Name | Divalproex sodium (Depacon, Depakene, Depakote, Depakote-ER) |
|---|---|
| Description | Branched chain fatty acid that undergoes oxidative metabolism and is highly protein bound. Amount of protein binding increases with dose. Available as 250 mg/5 mL syr; 250 mg capsules; 125 mg sprinkle capsules; 125, 250, 500 mg delayed-release tab; 250 and 500 mg extended-release tab, 100 mg/mL injectable solution. |
| Adult Dose | Initial dose: 5-15 mg/kg/d PO Maintenance dose: 15-60 mg/kg/d PO bid/qid |
| Pediatric Dose | 15-60 mg/kg/d PO bid/qid |
| Contraindications | Documented hypersensitivity; preexisting hepatotoxicity; age <2 y |
| Interactions | Cimetidine, salicylates, felbamate, and erythromycin may increase toxicity; rifampin may significantly reduce levels; in children, salicylates decrease protein binding and metabolism; may result in variable changes of carbamazepine concentrations with possible loss of seizure control; may increase diazepam and ethosuximide toxicity (monitor closely); may increase phenobarbital and phenytoin levels while either may decrease valproate levels; may displace warfarin from protein-binding sites (monitor coagulation tests); salicylates displace valproate from plasma protein-binding sites; methylphenidate may increase toxicity; may increase zidovudine levels |
| Pregnancy | D - Unsafe in pregnancy |
| Precautions | Common adverse effects include nausea, vomiting, drowsiness, tremor, dizziness, alopecia, weight gain, and thrombocytopenia at high serum concentrations Idiosyncratic adverse effects include hepatotoxicity (especially children aged <2 y), pancreatitis, and blood dyscrasias Thrombocytopenia and abnormal coagulation parameters have occurred—risk of thrombocytopenia increases significantly at total trough plasma concentrations >110 mcg/mL in females and 135 mcg/mL in males; at periodic intervals and prior to surgery, determine platelet counts and bleeding time before initiating therapy; reduce dose or discontinue therapy if hemorrhage, bruising, or hemostasis/coagulation disorder occur; hyperammonemia may occur, resulting in hepatotoxicity; monitor patients closely for appearance of malaise, weakness, facial edema, anorexia, jaundice, and vomiting |
| Drug Name | Gabapentin (Neurontin) |
|---|---|
| Description | Saturable gastric absorption with virtually no protein binding and no metabolism, primarily renal excretion. Available as 100, 300, 400 mg capsules, and 600 mg and 800 mg tab, and 50 mg/mL solution. |
| Adult Dose | 300-1200 mg PO tid |
| Pediatric Dose | 30-60 mg/kg/d PO tid |
| Contraindications | Documented hypersensitivity |
| Interactions | Antacids may reduce bioavailability significantly (administer at least 2 h following antacids) |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Common adverse effects include fatigue, somnolence, dizziness, ataxia, ankle swelling, and mild weight gain; caution in severe renal disease |
| Drug Name | Lamotrigine (Lamictal) |
|---|---|
| Description | Hepatically metabolized, moderate protein binding, with shorter half-life in presence of enzyme-inducing compounds. Available as 2, 5, and 25 mg dispersible tab; 25, 100, 150, and 200 mg tab. |
| Adult Dose | With valproic acid: 200 mg PO qd Without valproic acid: 300-500 mg/d PO bid |
| Pediatric Dose | With valproic acid: 1-5 mg/kg/d PO qd or divided bid Without valproic acid: 5-15 mg/kg/d PO qd or divided bid |
| Contraindications | Documented hypersensitivity |
| Interactions | Oral contraceptives may decrease lamotrigine levels; acetaminophen increases renal clearance, decreasing effects; similarly, phenobarbital and phenytoin increase metabolism, causing decrease in levels; valproic acid increases half-life |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Common adverse effects include dizziness, ataxia, sedation, diplopia, and nausea Idiosyncratic adverse effects include skin rash (risk of Stevens-Johnson especially increased in children, polytherapy with valproic acid, and with rapid dose titration), hepatotoxicity, and blood dyscrasias Caution in impaired renal or hepatic function |
| Drug Name | Phenobarbital (Barbital, Luminal, Solfoton) |
|---|---|
| Description | Highly metabolized, moderately protein bound with very long half-life and linear kinetics. Available as 16 mg capsule; 15, 20 mg/5 mL elixir; 15, 30, 60, 100 mg tab; 30 mg/mL, 60 mg/mL, 130 mg/mL injectable solution (all contain 69% propylene glycol). |
| Adult Dose | Loading dose: 10-20 mg/kg PO qd Maintenance dose: 1-3 mg/kg/d PO qd |
| Pediatric Dose | Neonates: 3-4 mg/kg/d PO qd <12 years: 3-7 mg/kg/d PO qd/bid |
| Contraindications | Documented hypersensitivity |
| Interactions | May decrease effects of chloramphenicol, digoxin, corticosteroids, carbamazepine, theophylline, verapamil, metronidazole, and anticoagulants (patients whose coagulation tests are stabilized on anticoagulants may require dosage adjustments if added to or withdrawn from their regimen); alcohol may produce additive CNS effects and death; chloramphenicol, valproic acid, and MAOIs may increase toxicity; rifampin may decrease effects; induction of microsomal enzymes may result in decreased effects of oral contraceptives in women (must use additional contraceptive methods to prevent unwanted pregnancy; menstrual irregularities may also occur) |
| Pregnancy | D - Unsafe in pregnancy |
| Precautions | Adverse effects include sedation, dizziness, mood change, insomnia, hyperkinesias, cognitive dysfunction, osteomalacia, Dupuytren contracture, frozen shoulder, and decreased libido Idiosyncratic adverse effects include skin rash, hepatotoxicity, and blood dyscrasias In prolonged therapy, evaluate hematopoietic, renal, hepatic, and other organ systems; caution in fever, hyperthyroidism, diabetes mellitus, and severe anemia, since adverse reactions can occur; caution in myasthenia gravis and myxedema |
| Drug Name | Phenytoin (Dilantin, Phenytek)/ Fosphenytoin (Cerebyx) |
|---|---|
| Description | Poorly soluble compound, highly protein bound, metabolized by cytochrome P-450 system, and has nonlinear pharmacokinetics. Available as 125 mg/5 mL susp; 50 mg chewable tab; 30 mg capsules; 100 mg capsules; 50 mg/mL injectable phenytoin solution (contains propylene glycol). Fosphenytoin is phosphorylated phenytoin, a prodrug that is highly soluble and converted rapidly to phenytoin; 50 mg phenytoin equivalent per mL solution (fosphenytoin). |
| Adult Dose | Loading dose: 15-20 mg/kg PO; 10-20 mg/kg IV PE Maintenance dose: 4-5 mg/kg/d PO qd/tid |
| Pediatric Dose | 4-7 mg/kg/d PO |
| Contraindications | Documented hypersensitivity |
| Interactions | Amiodarone, benzodiazepines, chloramphenicol, cimetidine, disulfiram, ethanol (acute ingestion), omeprazole, phenacemide, phenylbutazone, succinimides, fluconazole, isoniazid, metronidazole, miconazole, sulfonamides, trimethoprim, and valproic acid may increase toxicity; phenytoin decreases efficacy of oral contraceptives |
| Pregnancy | D - Unsafe in pregnancy |
| Precautions | Death from cardiac arrest has occurred after too-rapid IV administration of phenytoin, preceded sometimes by marked QRS widening (not reported with fosphenytoin) Blood dyscrasias have occurred and thus blood counts and urinalysis should be done when therapy is begun and at monthly intervals for several months thereafter; discontinue use if skin rash appears—do not resume use if rash is exfoliative, bullous, or purpuric; administer cautiously to patients with acute intermittent porphyria; exercise caution when administering to patients with diabetes, may raise blood glucose levels; discontinue drug if hepatic dysfunction occurs |
| Drug Name | Primidone (Mysoline) |
|---|---|
| Description | Metabolized to phenobarbital and phenylethylmalonamide (PEMA), which also possesses some weak anticonvulsant activity. Available as 250 mg/5 mL susp; 50, 250 mg tab. |
| Adult Dose | 250-2000 mg PO tid |
| Pediatric Dose | 10-25 mg/kg/d PO tid |
| Contraindications | Documented hypersensitivity |
| Interactions | Valproic acid increases toxicity; may decrease serum concentrations of ethosuximide, griseofulvin, valproic acid; phenytoin may decrease serum levels |
| Pregnancy | D - Unsafe in pregnancy |
| Precautions | Common adverse effects include sedation, dizziness, mood change, insomnia, hyperkinesias, cognitive dysfunction, osteomalacia, Dupuytren contracture, frozen shoulder, and decreased libido Idiosyncratic adverse effects include skin rash, hepatotoxicity, and blood dyscrasias |
| Drug Name | Tiagabine (Gabitril) |
|---|---|
| Description | GABA reuptake inhibitor, with its metabolism enhanced by cytochrome P-450 inducers. Highly protein bound. Available as 2, 4, 12, and 16 mg tab. |
| Adult Dose | 32-56 mg/d PO bid/qid |
| Pediatric Dose | 4-32 mg/kg/d PO bid/qid |
| Contraindications | Documented hypersensitivity |
| Interactions | Cleared more rapidly in patients treated with carbamazepine, phenytoin, primidone, or phenobarbital than in patients who have not received these drugs |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Common adverse effects include dizziness, asthenia, sedation, nervousness, irritability, and tremor, "knee-buckling" Patients receiving valproate monotherapy may require lower doses or slower dose titration of tiagabine for clinical response; moderately severe to incapacitating generalized weakness has been reported following administration of tiagabine in as many as 1% of patients with epilepsy—weakness may resolve after reduction in dose or discontinuation; should be withdrawn slowly to reduce potential for increased seizure frequency; possible nonconvulsive status epilepticus in patients noted to have new altered mental status; can trigger seizures in nonepileptic patients |
| Drug Name | Topiramate (Topamax) |
|---|---|
| Description | Undergoes moderate hepatic metabolism, and excreted largely by kidneys. Has low protein binding. Available as 15, 25 mg sprinkle capsules; 25, 100, and 200 mg tab. |
| Adult Dose | 200-600 mg/d PO bid |
| Pediatric Dose | 1-9 mg/kg/d PO bid |
| Contraindications | Documented hypersensitivity |
| Interactions | Phenytoin, carbamazepine, and valproic acid can decrease levels significantly; reduces digoxin and norethindrone levels; CNS depressants may have additive effect as well as other adverse cognitive or neuropsychiatric events, use with caution |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Common adverse effects include sedation, fatigue, psychomotor slowing, difficulty in concentrating, confusion, paresthesias, weight loss Risk of developing kidney stone increased 2-4 times that of untreated population; risk may be reduced by increasing fluid intake; caution in renal or hepatic impairment; carbonic anhydrase inhibitor chemistry also increases risk of angle-closure glaucoma, mild metabolic acidosis, and oligohidrosis |
| Drug Name | Oxcarbazepine (Trileptal) |
|---|---|
| Description | The pharmacological activity of oxcarbazepine is primarily performed by the 10-monohydroxy metabolite (MHD) of oxcarbazepine. May block voltage-sensitive sodium channels, inhibit repetitive neuronal firing, and impair synaptic impulse propagation. Anticonvulsant effect may also occur by affecting potassium conductance and high-voltage activated calcium channels. Drug pharmacokinetics are similar in older children (>8 y) and adults. Young children ( <8 y) have a 30-40% increased clearance compared with older children and adults. Available as 150-, 300-, and 600-mg tab and 300 mg/5 mL solution. |
| Adult Dose | 600-2400 mg/d PO bid |
| Pediatric Dose | 6-50 mg/kg/d PO bid |
| Contraindications | Documented hypersensitivity |
| Interactions | May decrease levels of dihydropyridine calcium antagonists and oral contraceptives; can reduce serum concentrations of carbamazepine, phenobarbital, phenytoin, and valproic acid; when oxcarbazepine is given in doses above 1200 mg/d, may increase phenytoin and phenobarbital serum concentrations significantly; oxcarbazepine may reduce serum concentrations of oral contraceptives; can increase clearance of felodipine |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Can cause cognitive side effects; in persons with impaired renal function (creatinine clearance <30 mL/min), oxcarbazepine dose should begin at one-half usual starting dose; dose increments should be made more slowly; oxcarbazepine can cause hyponatremia (sodium <125 mmol/L); among persons with hypersensitivity to carbamazepine, 25-30% will have hypersensitivity to oxcarbazepine; rapid withdrawal of oxcarbazepine can cause exacerbation of seizures; observe for side effects and monitor plasma levels of concomitant anticonvulsants during dose titration; idiosyncratic reactions reported (serious skin rash and hypersensitivity syndrome) |
| Drug Name | Levetiracetam (Keppra) |
|---|---|
| Description | Mechanism of action is unknown. Approved for adjunctive use in partial epilepsy. Available as 250-, 500-, 750-, and 1000-mg tab and 100 mg/mL solution. |
| Adult Dose | 1-3 g/d PO bid |
| Pediatric Dose | 10-30 mg/kg/d PO bid |
| Contraindications | Documented hypersensitivity |
| Interactions | None reported |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Caution in renal impairment; major side effects include somnolence, asthenia, incoordination, mild leukopenia (3%), and behavioral changes such as anxiety, hostility, emotional lability, depression and psychosis (1-2%), and depersonalization |
| Drug Name | Zonisamide (Zonegran) |
|---|---|
| Description | Indicated for adjunctive treatment of partial seizures with or without secondary generalization. Available as 25-, 50-, and 100-mg sprinkle cap. There is evidence that it is effective in myoclonic and other generalized seizure types as well. |
| Adult Dose | 200-600 mg/d PO qd |
| Pediatric Dose | 2-12 mg/kg/d PO bid |
| Contraindications | Documented hypersensitivity |
| Interactions | May increase serum carbamazepine levels; carbamazepine may increase zonisamide concentrations; phenobarbital may decrease zonisamide levels |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | May cause drowsiness, weight loss, ataxia, nausea, and slowing of mental activity As carbonic anhydrase inhibitor can increase risk of renal stones and oligohidrosis |
| Drug Name | Pregabalin (Lyrica) |
|---|---|
| Description | Structural derivative of GABA. Mechanism of action unknown. Binds with high affinity to alpha2-delta site (a calcium channel subunit). In vitro, reduces calcium-dependent release of several neurotransmitters, possibly by modulating calcium channel function. FDA approved for neuropathic pain associated with diabetic peripheral neuropathy or postherpetic neuralgia and as adjunctive therapy in partial-onset seizures. Available as 25, 50, 75, 100, 150, 200, 225, 300 mg capsules |
| Adult Dose | 150-600 mg/d PO divided bid/tid; initially 50 mg PO tid or 75 mg PO bid, if needed, may increase dose to maximum of 600 mg/d |
| Pediatric Dose | Not established |
| Contraindications | Documented hypersensitivity |
| Interactions | May cause additive effects on cognitive and gross motor functioning when coadministered with drugs that cause dizziness or somnolence |
| Pregnancy | C - Safety for use during pregnancy has not been established. |
| Precautions | Discontinue gradually (over a minimum of 1 wk) to minimize increased seizure frequency in patients with seizure disorders; may cause insomnia, nausea, headache, or diarrhea with abrupt withdrawal; common adverse effects include dizziness, somnolence, blurred vision, weight gain, and peripheral edema; may elevate creatinine kinase level, decrease platelet count, and increase PR interval; doses >300 mg/d associated with higher rate of adverse effects and treatment discontinuation; decrease dose with renal impairment (ie, CrCl <60 mL/min) |
Simple Partial Seizures excerpt
Article Last Updated: Jan 11, 2007