Long-term levetiracetam treatment of epilepsy patients: Clinical audit

PurposeThe long-term efficacy and tolerability of levetiracetam (LEV) was analysed in 218 epilepsy patients. One hundred and ninety-nine patients were treated for at least 6 months. We evaluated LEV efficacy for all types of seizures together, and for simple partial, complex partial and secondary generalized seizures individually.ResultsA significant decrease in the number of seizures occurred after 6 months of treatment (p < 0.001). Mean seizure frequency (irrespective of type) before LEV was 19.2 a month. The mean monthly frequency at 6, 12, 24 and 36 months dropped to 12.7, 10.5, 9.7 and 7.1 seizures a month, respectively. The mean percentage reduction in seizures at these times was 45.7, 52.1, 59.1 and 64.2% and the number of responding patients was 51.3, 54.2, 59.8 and 62.2%. The number of patients completely seizure free was 18.6, 16.7, 15.2 and 16.2%. We found similar results in the last three categories for partial simple, complex and secondary generalized seizures individually. Side effects in 18.3% of patients caused treatment discontinuation in 6.4%. The most frequent were somnolence, moodiness and dizziness. The retention rate at 6, 12, 24 and 36 months was 0.848, 0.72, 0.62 and 0.5, respectively.ConclusionsLEV is effective and well tolerated for long-term treatment of epilepsy.     

Evidence for sustained efficacy of levetiracetam as add-on epilepsy therapy

PURPOSE: To evaluate the long-term clinical usefulness of levetiracetam (LEV, Keppra((R))(1)) as add-on therapy in patients with refractory epilepsy. METHODS: Data for all 1422 patients with refractory epilepsy treated with LEV during the development program were analyzed for changes in seizure frequency per week, seizure freedom, and adverse events. RESULTS: Median percent reduction from baseline in seizure frequency per week over the whole treatment period was 39.6%, and no decrease over time was observed within each cohort exposed to LEV for durations ranging from 6 to 54 months. The median treatment period was 399 days (range 1-8 years). The proportion of responders during the first 3 months of LEV treatment was 39.2%. This proportion remained stable at 6 months (36.1%). Overall, 38.6 and 20.1% of patients had reductions in seizure frequency of at least 50 and 75%. Sixty-five (4.6%) patients were seizure-free over their entire treatment period, compared with 167 (11.7%) and 126 (8.9%) during their last 6 and 12 months of follow-up. Ninety-seven (19.8%) of 491 patients who received only one other antiepileptic drug (AED) in addition to LEV were seizure-free during their last 6 months. The proportion of patients who reduced their number of concomitant AEDs was 14.4% (205 patients), while 5.5% (79 patients) were treated with LEV only at the end of follow-up. Accidental injury (28.0%), infection (26.6%), headache (25.8%), somnolence (23%), asthenia (22.6%), and dizziness (18.9%) were among the most common adverse events. CONCLUSION: LEV offers sustained efficacy in patients with refractory partial seizures, and its long-term tolerability is similar to that seen in the short-term placebo-controlled trials.     

Efficacy and tolerability of levetiracetam in children younger than 4 years: a retrospective review

PURPOSE: To review our experience of the efficacy and tolerability of levetiracetam (LEV) in children younger than 4 years. METHODS: We used retrospective chart review to identify 122 children with seizures who were younger than 4 years and followed for >or=6 months. Efficacy was evaluated on the basis of the occurrence and durability of seizure remission. Tolerability was based on parent- and patient-reported side effects. RESULTS: Seventy (57%) subjects achieved seizure remission, and 52 (43%) did not. In univariate analysis, those achieving seizure remission were more likely to have partial epilepsy, require lower maintenance doses of LEV, and have fewer than two seizures per month at initiation of the medication. Only seizure frequency at initiation of LEV remained significant in multivariate analysis. The median duration of seizure freedom (8.9 month) was not influenced by age, epilepsy type, gender, or pretreatment seizure frequency. The dose of LEV was the only significant predictor of the duration of seizure remission, with longer duration of seizure remission seen in those taking <30 mg/kg/day compared with those taking > 30 mg/kg/day (median, 12.8 months vs. 3 months; p<0.0001). Side effects of LEV occurred in 34% of subjects but required discontinuation in only 16%, most commonly because of behavioral disturbances. CONCLUSIONS: LEV is an effective medication in children younger than 4 years and at doses lower than previously reported. It also well tolerated, suggesting that it represents an important option for the treatment of epilepsy in this age group.     

Levetiracetam in the treatment of childhood epilepsy

Epilepsy is a common pediatric neurologic disorder that is difficult to manage in a substantial portion of children. Levetiracetam (LEV) is a novel antiepileptic drug (AED) that has recently been approved as add-on treatment for various seizure types in epilepsy populations that include children: for refractory partial seizures in epilepsy patients ≥4 years old, for myoclonic seizures in juvenile myoclonic epilepsy patients ≥12 years old, and for primary generalized tonic-clonic seizures in idiopathic generalized epilepsy patients (≥6 years old with FDA approval; ≥12 years old with EMEA approval). A review of published pediatric studies indicates that the efficacy of LEV is best established for partial seizures; however, results from recent double-blind and open-label trials indicate that adjunctive LEV also controls generalized seizures – particularly myoclonic and generalized tonic-clonic – in children and adolescents with primary generalized epilepsy. LEV was well-tolerated in pediatric studies. The most common adverse events (AEs) reported were sedation related. Behavioral AEs were among the most commonly reported events in some trials; conversely, improvements in behavior and cognition were also frequently reported. LEV appears to be a safe and effective AED with unique characteristics that benefit the treatment of children with epilepsy.     

Levetiracetam and partial seizure subtypes: pooled data from three randomized, placebo-controlled trials

PURPOSE: To determine the effect of levetiracetam (LEV) on partial seizure subtypes (simple partial, complex partial, and secondarily generalized seizures) in patients with refractory epilepsy. METHODS: Pooled results from three placebo-controlled trials were analyzed. RESULTS: A statistically significant reduction in the frequency of all partial seizures and all seizure subtypes was observed in the LEV group (p < 0.001 vs. placebo). The proportion of patients in whom secondarily generalized seizures could be prevented over and above the reduction of partial seizures was significantly greater in the LEV group as compared with placebo, with an odds ratio of 1.83 [95% confidence interval (CI), 1.10-3.05]. CONCLUSIONS; LEV reduces frequency of simple and complex partial seizures. In addition, it demonstrates a specific, independent reduction of secondarily generalized seizures.     

Clinical experience of levetiracetam monotherapy for adults with epilepsy: 1-year follow-up study.

We identified 46 patients with a history of partial seizures, with and without secondarily generalization, who received levetiracetam (LEV) (Keppra) monotherapy. Patients began LEV either as first line therapy (n=11) or were converted to LEV monotherapy (n=35) after failing prior antiepileptic medications (AEDs). Patients were followed up to 12 months after LEV started. The majority of these patients were able to continue on LEV and a small number of patients discontinued LEV secondary to lack of efficacy. One third of the non-seizure free group at 6 months of follow-up had worse seizure control at 12 months and two thirds had the same or better seizure control. Our 1-year follow-up data of LEV as monotherapy suggests that LEV can be effective and well tolerated in adults with either new or difficult to control epilepsy. A prospective, large, long-term double-blind study is needed to confirm this finding.     

Levetiracetam in patients with refractory epilepsy: results of the SKATE trial in Austria, Germany and Switzerland.

PURPOSE: To further evaluate the safety, efficacy and optimal dose of levetiracetam (LEV) in daily clinical practice among patients with uncontrolled partial epilepsy with or without secondary generalization. METHODS: In this phase IV, open-label, 16-week community-based study, 178 at least 16-year-old patients with refractory focal epilepsy were treated with 1000, 2000 or 3000 mg levetiracetam as adjunctive therapy. All patients started with 500 mg LEV b.i.d. (1000 mg/day); the dose was adjusted in 2-week intervals up to 1500 b.i.d. (3000 mg/day) depending on seizure control and tolerability. The main objectives were the adverse events, the percentage reduction in partial and total seizure frequency per week from baseline and the retention rate, defined as the percentage of patients taking LEV at the end of the 16-week treatment period. RESULTS: Of the 178 patients who took at least one dose of LEV 151 completed the study. Thus, the retention rate (number of patients taking LEV at the end of the 16-week treatment period) was 84.8%. Most frequently reported adverse events were asthenia, dizziness, headache, nausea, somnolence and hostility; the majority of these events were of mild to moderate intensity. The seizure-free rate of the ITT population with focal seizures was 16.7%, for all seizures 16.6%; the median reduction of focal seizure frequency was 47.6%, and 46.5% for all seizures. The 50% responder rate was 46.6% for focal seizures and 45.1% for all seizures. CONCLUSION: Add-on treatment with LEV in patients with refractory partial epilepsy was safe and effective in this study.     

Monotherapy for partial epilepsy: focus on levetiracetam

Levetiracetam (LEV), the S-enantiomer of alpha-ethyl-2-oxo-1-pyrollidine acetamide, is a recently licensed antiepileptic drug (AED) for adjunctive therapy of partial seizures. Its mechanism of action is uncertain but it exhibits a unique profile of anticonvulsant activity in models of chronic epilepsy. Five randomized, double-blind, placebo-controlled trials enrolling adult or pediatric patients with refractory partial epilepsy have demonstrated the efficacy of LEV as adjunctive therapy, with a responder rate (>/=50% reduction in seizure frequency) of 28%-45%. Long-term efficacy studies suggest retention rates of 60% after one year, with 13% of patients seizure-free for 6 months of the study and 8% seizure-free for 1 year. More recent studies illustrated successful conversion to monotherapy in patients with refractory epilepsy, and its effectiveness as a single agent in partial epilepsy. LEV has also efficacy in generalized epilepsies. Adverse effects of LEV, including somnolence, lethargy, and dizziness, are generally mild and their occurrence rate seems to be not significantly different from that observed in placebo groups. LEV also has no clinically significant pharmacokinetic interactions with other AEDs, or with commonly prescribed medications. The combination of effective antiepileptic properties with a relatively mild adverse effect profile makes LEV an attractive therapy for partial seizures.     

An open-label study of levetiracetam at individualised doses between 1000 and 3000 mg day(-1) in adult patients with refractory epilepsy.

BACKGROUND: The novel antiepileptic drug (AED) levetiracetam (LEV, Keppra) is indicated as adjunctive therapy for partial epilepsy. The primary aim of this study was to measure the safety and tolerability of LEV individualised dosing in a heterogeneous refractory epilepsy population.METHODS: LEV was evaluated in a 10- to 16-week open-label, multicentre study in adult patients with epilepsy refractory to previous treatment with at least two AEDs. Individualised LEV doses up to 3000 mg x day(-1) were determined in an initial up-titration phase, and optimal doses were administered as adjunctive treatment during an 8- to 10-week evaluation period. Concomitant AEDs and their doses could not be changed during the study. Safety and tolerability were monitored by expression of adverse events as well as by retention rate. The effect of LEV on concomitant AED concentration was also studied. Efficacy was assessed using global clinical evaluation (GCE) scores, seizure frequency, and >or=50% responder rate. RESULTS: LEV therapy was initiated in 219 patients; 183 had localisation-related epilepsy and 37 had generalised epilepsy. In one patient, epileptic syndrome was defined as both localisation-related and generalised. About 81.7% (179/219) continued and completed treatment throughout the study, and 79% (172/219) chose to continue LEV in a follow-up study. The most common adverse events were asthenia, dizziness, and somnolence. Most adverse events occurred during up-titration. LEV treatment did not alter the concentration of concomitant AEDs. LEV improved GCE scores in 79.5% (152/191) of patients. LEV reduced the median total seizure frequency of all patients from a median of 2.25 seizures per week at baseline (n=219) to 1.10 seizures per week during the evaluation period (n=191 patients with at least one seizure count during evaluation). The >or=50% responder rate was 48.2% for all seizure types, 49.4% for partial-onset, and 51.4% for generalised-onset seizures. Throughout the evaluation period (i.e. from the start of the evaluation period until completion or early discontinuation), 26/191 (13.6%) had a 100% reduction in total seizure frequency, while in a follow-up study, 10.5% (18/172) were seizure-free for at least 6 months and 6.4% (11/172) were seizure-free for at least 1 year. CONCLUSION: LEV was well tolerated, as evidenced by limited adverse event reporting and the high retention rate, and appeared effective in both generalised and partial epilepsy.     

Levetiracetam during 1-year follow-up in children, adolescents, and young adults with refractory epilepsy

PURPOSE: To evaluate the efficacy and safety of levetiracetam (LEV) in refractory crypto/symptomatic, partial or generalised epilepsy in children, adolescents and young adults. METHODS: We performed a prospective open label add-on study in 99 patients (age 12 months to 32 years, mean 14 years) with partial or generalised, crypto/symptomatic seizures. Levetiracetam was added to no more than two baseline AEDs and the efficacy was rated according to seizure type and frequency. RESULTS: LEV was initiated at the starting dose of 10mg/kg/day with 5-day increments up to 50 mg/kg/day, unless it was not tolerated. Concomitant therapy was generally not modified throughout the study. After a mean follow-up period of 6.7 months (range 3 weeks to 29 months), 11 patients (11.1%) were free of seizures (cryptogenic partial epilepsy, 5; symptomatic partial epilepsy, 6). A more than 75% seizure decrease was found in 14 patients (14.1%) and >50% in 8 (8.1%). Seizures were unchanged in 38 (38.4%), and worsened in 23 (23.2%). Mild and transient adverse side effects were found in 17 patients (17.2%), mostly represented by irritability and drowsiness. CONCLUSION: LEV appears to be well tolerated in children and adolescents with severe epilepsy and seems to be a broad spectrum AED, though in our experience, it was more effective against partial seizures with or without secondarily generalisation. LEV efficacy in other epilepsy syndrome should be evaluated further in homogeneous, more selected patients.     

Use of topiramate in childhood generalized seizure disorders

Topiramate is a sulfamate derivative of the naturally occurring monosaccharide D-fructose. It was initially approved in the United States as adjunctive therapy for partial seizures in 1997. However, there is increasing evidence that it is effective in the treatment of generalized seizures and epilepsy syndromes. Initially, open-label studies using topiramate as add-on therapy in children with refractory generalized seizure types were performed. These showed improvement in patients with the following generalized seizure types: typical and atypical absence, atonic, myoclonic, generalized tonic-clonic, and juvenile myoclonic epilepsy. Double-blind, placebo-controlled multicentered studies in patients with refractory primary generalized tonic-clonic seizures and epilepsy syndromes were performed. The median reduction in seizure frequency for primary generalized tonic-clonic seizures was 56.7% for topiramate and 9% for placebo. Additionally, 13.6% of topiramate-treated patients were primary generalized tonic-clonic seizure free for the study period. In the topiramate-treated juvenile myoclonic epilepsy patients, primary generalized tonic-clonic seizures were reduced > 50% in 73% of patients. Open-label extension showed that primary generalized tonic-clonic seizures were reduced >50% in 63% of topiramate-treated patients for > or = 6 months, and 16% were primary generalized tonic-clonic seizure free > or = 6 months. Accumulating evidence suggests that topiramate has a broad spectrum of antiepileptic effect. Moreover, life-threatening organ toxicity has not been attributed to topiramate. Topiramate is an effective treatment for refractory generalized seizure types and epilepsy syndromes encountered in children.     

Levetiracetam reduces frequency and duration of epileptic activity in patients with refractory primary generalized epilepsy.

PURPOSE: Levetiracetam (LEV) is a new antiepileptic drug highly effective as add-on treatment in refractory partial epilepsies. In animal models, LEV is effective against absence seizures. A limited number of case reports and series indicate that LEV reduces seizure frequency in patients with generalized epilepsies. METHOD: We evaluated with continuous EEG eight adult patients with idiopathic generalized epilepsy (IGE). All patients were refractory to the conventional therapy for IGE. Four patients received LEV as add-on therapy, and in four, a conversion to LEV monotherapy was undergone. Epileptic activity was analyzed in order to determine spike-wave density as well as median and maximal duration of spike-wave discharges. Each patient underwent a 24h EEG baseline monitoring before starting LEV therapy. A second 24h EEG examination was performed after a mean follow-up period of 136 days. RESULTS: Spike-wave density (spikes/h) was reduced by 78% after LEV administration. Median spike-wave duration decreased by 72% (p < 0.05). Maximal spike-wave duration was 6s before, and 1.5s after LEV with a percentage change of 81% (p < 0.05). The four patients on LEV monotherapy evidenced also a considerably improvement after conversion. CONCLUSIONS: This study showed that LEV produces a consistent long-term reduction of interictal epileptic activity in patients with refractory IGE. The reduction in the spike-wave activity additionally correlated with a clinically relevant antiepileptic effect. Our results support the concept that LEV could be an alternative therapy in primary generalized epilepsies.     

Efficacy and safety of levetiracetam in infants and young children with refractory epilepsy.

The aim of this multicentric, retrospective, and uncontrolled study was to evaluate the efficacy and safety of levetiracetam (LEV) in 81 children younger than 4 years with refractory epilepsy. At an average follow-up period of 9 months, LEV administration was found to be effective in 30% of patients (responders showing more than a 50% decrease in seizure frequency) of whom 10 (12%) became seizure free. This efficacy was observed for focal (46%) as well as for generalized seizures (42%). In addition, in a group of 48 patients, we compared the initial efficacy (evaluated at an average of 3 months of follow-up) and the retention at a mean of 12 months of LEV, with regard to loss of efficacy (defined as the return to the baseline seizure frequency). Twenty-two patients (46%) were initial responders. After a minimum of 12 months of follow-up, 9 of 48 patients (19%) maintained the improvement, 4 (8%) of whom remained seizure free. A loss of efficacy was observed in 13 of the initial responders (59%). Maintained LEV efficacy was noted in patients with focal epilepsy and West syndrome. LEV was well tolerated. Adverse events were seen in 18 (34%) patients. The main side effects were drowsiness and nervousness. Adverse events were either tolerable or resolved in time with dosage reduction or discontinuation of the drug. We conclude that LEV is safe and effective for a wide range of epileptic seizures and epilepsy syndromes and, therefore, represents a valid therapeutic option in infants and young children affected by epilepsy.     

Loss of the initial efficacy of levetiracetam in patients with refractory epilepsy

PurposeThe efficacy and safety of the anti-convulsive drug levetiracetam (LEV) has been well documented but few clinical studies have investigated tolerance to LEV. The aim of this study was to evaluate the loss of the initial efficacy of LEV in adult patients with refractory partial-onset seizures.MethodsWe enrolled patients with refractory partial epilepsy who were started on add-on LEV treatment. The efficacy of LEV was evaluated every three months and the seizure frequency was decided by the average number of monthly seizures. A responder was defined as a patient with a ≥50% reduction in seizure frequency from the baseline. Seizure freedom was defined as a seizure-free status from the beginning of LEV treatment to the evaluation period. Loss of the initial efficacy was defined as a shift from responder status during the first three months of LEV treatment to non-responder status during the follow-up period.ResultsA total of 95 epilepsy patients were analyzed. During the first three months of LEV treatment, 50 (52.6%) of the 95 patients were responders with a ≥50% seizure reduction. Nine patients (18.0%) showed a loss of initial efficacy during the second three-month period. In contrast, only two (4.0%) of the non-responders during the first three months became responders during the next three months. However, this difference did not reach statistical significance (P = 0.054). Based on Kaplan–Meier survival estimates, 49.2% of the patients who initially responded to LEV treatment during the first three months were predicted to lose this response at 42 months. Loss of the initial efficacy of LEV treatment occurred mostly within 18 months.ConclusionThis study suggests that the occurrence of tolerance is more common than late gain of efficacy of treatment although larger prospective studies would have to be carried out to prove this observation.     

Levetiracetam in juvenile myoclonic epilepsy: long-term efficacy in newly diagnosed adolescents

The aim of this study was to evaluate the efficacy and tolerability of levetiracetam (LEV) monotherapy in juvenile myoclonic epilepsy (JME). The study group consisted of 32 patients with epilepsy (20 males, 12 females) with a mean age of 13 years 3 months (SD 7y 11mo) at seizure onset. LEV was administered as the first drug; all patients were followed up at 6 and 12 months. The dose that achieved seizure control ranged from 1000 to 2500mg/daily. At 6-month evaluation: 15 patients were seizure free; 14 patients were responders (>50% reduction in seizures); and three patients had marginal effects (<50% reduction of seizures). At 12-month evaluation: 29 patients were seizure free; three patients were responders. No patients reported adverse events. These data provide preliminary evidence that LEV may be effective for treating patients with newly diagnosed JME.     

Evaluation of refractory epilepsy treated with vagus nerve stimulation for up to 5 years

We assessed the long-term efficacy of vagus nerve stimulation (VNS) in 64 refractory epilepsy patients. After implantation, intermittent stimulation was delivered and seizure frequency and severity were counted. Average treatment time was 20 months. Nineteen of 47 patients with partial seizures, five of nine patients with idiopathic generalized seizures, and five of eight patients with Lennox-Gastaut syndrome had >50% seizure reduction. Side effects were mild. VNS is a safe and effective treatment for refractory epilepsy.     

Encephalopathy induced by levetiracetam added to valproate

Background –  We report on the manifestation of a levetiracetam (LEV)-induced encephalopathy.
Findings –  A 28-year-old man suffering from idiopathic epilepsy with generalized seizures was treated with LEV (3000 mg) added to valproate (VPA) (2000 mg). Frequency of generalized tonic-clonic seizures increased from one per 6 months to two per month. Neuropsychological testing showed impaired word fluency, psychomotor speed and working memory. The interictal electroencephalogram (EEG) showed a generalized slowing to 5 per second theta rhythms with bilateral generalized high-amplitude discharges.
Outcome –  Following discontinuation of LEV, EEG and neuropsychological findings improved and seizure frequency decreased.     

Efficacy and safety of levetiracetam as adjunctive treatment of refractory partial seizures in a multicentre open-label single-arm trial in Korean patients.

This prospective, open-label study evaluated the efficacy and safety of adjunctive levetiracetam (LEV) in Korean adults with uncontrolled partial epilepsy. Study patients had to have an average of at least 1 and not more than 14 partial seizures per month (averaged over a 3-month historical baseline) despite the use of one or two AEDs. Patients initially received LEV 1000 mg/day (administered bid) and could increase to 2000 mg/day after 2 weeks, and to 3000 mg/day after another 2 weeks, to obtain adequate seizure control. During the 12-week maintenance period, the dose of LEV could be increased or decreased once if seizure control was insufficient or tolerability warranted, respectively. Seizure count and adverse events (AEs) were recorded by patients. Global evaluation scale (GES) and quality of life (QOLIE-31) were also evaluated. A total of 100 patients were enrolled and 92 patients completed the study. The median percent reduction in weekly seizure frequency over the treatment period was 43.2%. The >or=50% and >or=75% responder rates were 45.4% and 36.1%, respectively. Seizure freedom throughout the 16-week treatment period was observed in 17 patients. On investigator's GES, 81 patients were considered improved, with 41 patients showing marked improvement. Most QOLIE-31 scales improved significantly. Treatment-emergent AEs were reported in 59 patients. Three most common AEs were somnolence (36%), dizziness (12%), and headache (8%). Adjunctive LEV therapy was effective and well-tolerated in Korean adults with refractory partial epilepsy.     

脑卒中后癫痫50例临床研究

目的探讨脑卒中后癫痫的临床特点，癫痫对脑卒中恢复期神经功能康复的影响。方法50例脑卒中后继发癫痫患者进行发作部位、类型、治疗时间及效果等分析，并按病情轻、中、重三组进行功能康复评分。结果脑卒中后癫痫发生率5．1%（50／980），其中早发癫痫72％（36／50），迟发癫痫28％（14／50）。皮层病灶继发癫痫72％（36／50），皮层下病灶继发癫痫占28％（14／50）。早发癫痫中全身发作27例．部分性发作9例，迟发癫痫中全身发作4例，部分性发作10例。癫痫组神经功能缺损评分均差于对照绀组（P〈0．05），结论脑卒中后癫痫皮层病灶多见，早发癫痫以全身发作为主，迟发癫痫以部分发作为主。脑卒中合并癫痫患者的治疗效果差于对照组，抗癫痫治疗有利于神经功能康复。     

Sleep and sleep deprived EEG in partial and generalized epilepsy

Sleep and sleep deprivation are often used for EEG activation in epilepsy. We compared postprandial naps and day-long sleep deprived EEGs in 36 patients with generalized seizures, 57 complex partial seizure patients, and 7 individuals with mixed seizure disorders. Ten of 36 generalized seizure patients had normal sleep and sleep deprived EEGs, while both were normal in 16 of 57 partial seizure patients. Both were abnormal in 18 of 36 generalized and 22 of 57 partial epileptics. Seven generalized seizure patients had epileptiform discharges or seizures during afternoon naps but normal sleep deprived EEGs. No partial seizure patients had normal sleep deprived EEGs and abnormal nap, but 29 of 57 had abnormalities or seizures only with sleep deprivation. All 7 mixed seizure patients had abnormal sleep and sleep deprived studies, and 6 had seizures, 4 on both studies. Natural sleep may facilitate the appearance of generalized seizures or epilepti-form discharges, while sleep deprivation may accentuate the yield of EEG abnormality in partial epilepsy. Either is likely to be abnormal in patients with mixed seizures and encephalopathy. Natural sleep and sleep deprived EEGs are an appropriate combination in the evaluation of refractory seizures.