Phenobarbitone, phenytoin, carbamazepine, or sodium valproate for newly diagnosed adult epilepsy: a randomised comparative monotherapy trial.

Recent studies have shown that most newly diagnosed epileptic patients can be satisfactorily treated with a single antiepileptic drug. We therefore undertook a prospective randomised pragmatic trial of the comparative efficacy and toxicity of four major antiepileptic drugs, utilised as monotherapy in newly diagnosed epileptic patients. Between 1981 and 1987 243 adult patients aged 16 years or over, newly referred to two district general hospitals with a minimum of two previously untreated tonic-clonic or partial with or without secondary generalised seizures were randomly allocated to treatment with phenobarbitone, phenytoin, carbamazepine, or sodium valproate. The protocol was designed to conform with standard clinical practice. Efficacy was assessed by time to first seizure after the start of treatment and time to enter one year remission. The overall outcome with all of the four drugs was good with 27% remaining seizure free and 75% entering one year of remission by three years of follow up. No significant differences between the four drugs were found for either measure of efficacy at one, two, or three years of follow up. The overall incidence of unacceptable side effects, necessitating withdrawal of the randomised drug, was 10%. For the individual drugs phenobarbitone (22%) was more likely to be withdrawn than phenytoin (3%), carbamazepine (11%), and sodium valproate (5%). In patients with newly diagnosed tonic-clonic or partial with or without secondary generalised seizures, the choice of drug will be more influenced by considerations of toxicity and costs.     

A prospective study between carbamazepine, phenytoin and sodium valproate as monotherapy in previously untreated and recently diagnosed patients with epilepsy.

One hundred and eighty one patients with previously untreated epilepsy were randomised to sodium valproate, phenytoin or carbamazepine as monotherapy and followed up for a median period which ranged from 14 to 24 months. All three drugs were highly effective in the control of generalised seizures but less effective for partial seizures. Excellent or good control was achieved with therapeutic levels of sodium valproate and carbamazepine, but with subtherapeutic levels of phenytoin.     

SODIUM VALPROATE IN the TREATMENT of RESISTANT EPILEPSY

A series of 115 patients was treated with sodium valproate (Epilim) for periods ranging from 6 to 24 months and in dosages ranging from 400 mg to 2400 mg daily. All but six of these patients had intractable epilepsies and had been previously treated unsuccessfully with other anti-epileptic agents. Eighty patients had generalised seizures and 35 had partial seizures which, in 26 cases, were secondarily generalised. Reduction of seizure frequency by over 50 per cent occurred in about 70 per cent of patients with generalised seizures but in only 37 per cent of those with partial seizures. A number of patients reported increased alertness, improvement of mood, increased appetite and improved performance at school. the adverse effects encountered were gastro-intestinal symptoms, weight gain and hair loss.     

Rufinamide for the adjunctive treatment of partial seizures in adults and adolescents: A randomized placebo-controlled trial

Purpose:   To evaluate efficacy and safety of adjunctive treatment with rufinamide 1600 mg twice daily in subjects aged ≥16 years with refractory partial seizures.
Methods:   This double-blind, placebo-controlled, randomized, parallel-group, multicenter trial included an 8-week baseline phase and a 13-week double-blind phase. Treatment was initiated with rufinamide 400 mg twice daily or placebo; rufinamide was titrated to 1600 mg twice daily. Percentage change in partial seizure frequency was the primary outcome measure. Secondary outcome measures included total partial seizure frequency and the percentage of subjects experiencing a ≥50% reduction in partial seizure frequency.
Results:   Three hundred thirteen subjects were randomized; 156 subjects received rufinamide and 157 received placebo. Rufinamide-treated subjects experienced a 20.4% median reduction in partial seizure frequency relative to baseline, while placebo-treated subjects had an increase of 1.6% (p = 0.02). Exclusion of subjects taking carbamazepine in a post hoc analysis resulted in a reduction of 29.2% versus 0.7% in the placebo group (p = 0.05), whereas the treatment difference in subjects taking carbamazepine was not significant. Of rufinamide-treated subjects, 28.2% experienced a ≥50% decrease in partial seizure frequency versus 18.6% of placebo-treated subjects (p = 0.04). The most common adverse events associated with rufinamide treatment were dizziness, nausea, diplopia, and ataxia; they occurred primarily during the titration phase.
Discussion:   Adjunctive therapy with rufinamide 3200 mg/day compared with matching placebo demonstrated efficacy and was generally well tolerated in adults with partial seizures. Further study of this agent in adults with partial seizures taking a range of baseline AEDs is warranted.     

The cognitive effects of oxcarbazepine versus carbamazepine or valproate in newly diagnosed children with partial seizures

OBJECTIVE: To investigate the effect of oxcarbazepine against standard antiepileptic drug therapy (carbamazepine and valproate) on cognitive function in children and adolescents (aged 6 to <17 years) with newly diagnosed partial seizures. METHODS: A multicentre, open-label, randomised, active-control, three-arm, parallel-group, 6-month study. The primary cognitive variable, the Computerized Visual Searching Task (CVST), assessed mental information processing speed and attention. Secondary variables included additional tests assessing psychomotor speed, alertness, memory and learning, and non-verbal intelligence. RESULTS: Of 112 patients randomised, 99 completed the study. The dropout rate was 11.6%; 13 patients discontinued due to adverse events (n=5) or unsatisfactory therapeutic effect (n=8). Mean CVST time decreased in all groups, indicating an improvement of mental processing speed and no cognitive impairment in any treatment group. No statistically significant difference was observed between oxcarbazepine and combined carbamazepine/valproate. Analysis of secondary variables did not show statistically significant differences between oxcarbazepine, carbamazepine and valproate. Analysis of intelligence test results showed that the number of correct answers increased at end point in all groups. The percentage of patients remaining seizure free throughout treatment was comparable across all groups (oxcarbazepine 58%; carbamazepine 46%; valproate 54%; carbamazepine/valproate 50%). The most common adverse events were fatigue and headache for oxcarbazepine, fatigue and rash for carbamazepine, and headache, increased appetite and alopecia for valproate. CONCLUSION: Oxcarbazepine treatment over 6 months does not display any differential effects on cognitive function and intelligence in children and adolescents with newly diagnosed partial seizures relative to standard antiepileptic drug therapy. No impairment in cognitive function was observed in any treatment group over a 6-month period.     

Lamotrigine: single-dose pharmacokinetics and initial 1 week experience in refractory epilepsy

Twenty-three residential patients on chronic antiepileptic drugs (AEDs) were entered into an open study of 4 weeks duration. Baseline variables and seizure frequency were determined in the first week. All patients received a single dose of lamotrigine in the second week to determine single-dose pharmacokinetic parameters. Twenty patients then received daily or twice daily lamotrigine for a week. Post-treatment seizure frequency was observed for a further week. Patients taking liver enzyme inducing antiepileptic drugs showed a mean lamotrigine plasma elimination half-life (T1/2) of 14 h (+/- 7) (T1/2 of normal volunteers = 24 h) and those taking sodium valproate and an inducing AED showed a mean lamotrigine T1/2 of 30 h (+/- 10). The plasma concentrations of co-administered sodium valproate, phenytoin, carbamazepine, phenobarbitone and primidone were not altered by 1 week lamotrigine dosing. There was a significant reduction in complex partial seizures in the treatment week compared with baseline. Some patients showed a marked increase in seizure frequency on stopping lamotrigine. There was an increase in reports of drowsiness during lamotrigine administration, but there were no clinically significant changes in any safety measure.     

Vigabatrin and lamotrigine in refractory epilepsy.

Epilepsy arises from an imbalance of inhibitory and excitatory influences in the brain. Vigabatrin (VIG) decreases the breakdown of the inhibitory neurotransmitter gamma-aminobutyric acid, whereas lamotrigine (LTG) reduces presynaptic excitatory amino acid release. 22 patients with refractory epilepsy, treated with an anticonvulsant regimen containing VIG, entered a balanced, double blind, placebo controlled, crossover trial of additional LTG. Treatment periods of 12 weeks (25 mg, 50 mg, 100 mg LTG twice daily for four weeks at each dose, and matched placebo) were followed by wash out intervals of four weeks. 14 of the 20 patients completing the study improved, resulting in a significant fall in seizure days and numbers. Analysis of seizure type confirmed a beneficial effect on partial and secondary generalised tonic-clonic seizures. At the highest LTG dose (200 mg daily) there was a median fall of 37% in seizure count with nine (45%) patients reporting > 50% reduction. Three of these patients were seizure free during this month of treatment. Side effects were minimal throughout the study. Concentrations of other antiepileptic drugs, including those of carbamazepine 10,11-epoxide, were not modified by LTG. This study suggests a substantial efficacy for a regimen containing VIG and LTG. Combinations of drugs with complementary modes of action may provide a rational pharmacological approach to the management of refractory epilepsy.     

Double-blind, placebo controlled, crossover study of lamotrigine in treatment resistant partial seizures.

The results of a multicentre, randomised, double-blind, placebo controlled, crossover trial of lamotrigine as add-on therapy in patients with partial seizures poorly controlled by established antiepileptic drugs (AEDs) are presented. The study consisted of two 12 week treatment periods each followed by a four week washout period. During the lamotrigine treatment phase, patients received 150 mg or 300 mg daily dose depending on their concomitant AEDs to achieve concentrations in the range 1-3 mg/L. Forty one patients were entered at four centres and all patients entered completed the study. There was a highly significant (p < 0.001) decrease in total seizure counts on lamotrigine compared with placebo. Overall, 22% of patients experienced at least a 50% reduction in the total numbers of all seizures types on lamotrigine, compared with none on placebo. When the total numbers of partial seizures (simple and complex partial) were analysed there was also a significant (p < 0.05) reduction in seizure counts on lamotrigine compared with placebo. When total numbers of secondarily generalised seizures were compared the trend for a reduction in this seizure type did not achieve significance (0.05 < p < 0.1). Concomitant AED plasma concentrations were virtually unchanged. It is concluded that lamotrigine is an effective AED in the treatment of therapy-resistant partial seizures.     

Valproate Monotherapy in 30 Patients with Partial Seizures

This retrospective pilot study describes 30 patients diagnosed and treated for complex partial seizures (CPS) and simple partial seizures (SPS) with and without generalization who received valproate (VPA) monotherapy after lack of response or allergic reaction for carbamazepine (CBZ), phenytoin (PHT), or phenobarbital (PB). Seizures were tabulated daily on seizure calendars by the patients. Three time periods were examined for seizure frequency, 90 days before VPA treatment and 90 and 180 days after VPA treatment. Twenty-two were "controlled" or "improved" (reduction of seizure activity by greater than or equal to 51%) 6 months following the initiation of VPA. VPA was particularly effective in 17 patients who had secondarily generalized tonic-clonic seizures (GTCS) as a subtype of partial seizures. Failure of response to VPA in eight patients appears to be related to their type of partial seizure (SPS or CPS alone, without GTCS) and duration of uncontrolled recurrent seizures. Etiology and compliance were not related to treatment failure. This study supports the need for a double-blind controlled trial with VPA in patients with partial seizures.     

Lamotrigine as an add-on drug in typical absence seizures

Introduction - Lamotrigine is licenced in many countries for use in patients with partial seizures. Evidence suggests that it may also be effective in generalised epilepsies. Material & methods - We analysed retrospectively our patients with idiopathic generalised epilepsy with refractory absences. Results - Fifteen patients with idiopathic generalised epilepsies were identified who had been treated with lamotrigine for 3 months or more. All patients were also treated with sodium valproate. Fourteen patients had active absences. Nine (64%) had a total or virtual cessation of absences and in a further patient they became milder and less frequent. One patient reported an increase in seizures. The effective dose of lamotrigine was 1.6-3.0 mg/kg/day in children and 25-50 mg/day in adults. Patients who responded did so after the first or second dose. Lamotrigine was well tolerated. Conclusion - Low-dose lamotrigine added to sodium valproate appears to be effective in typical absence seizures. A therapeutic interaction of the two drugs seems likely.     

A controlled study with taltrimide and sodium valproate: valproate effective in partial epilepsy

Taltrimide was compared with valproate and placebo in 17 patients with intractable epilepsy being on carbamazepine monotherapy. Taltrimide (400 mg/day), valproate (1000 mg/day) or placebo were added to the treatment for periods of 3 months using a randomized cross-over design. Serum carbamazepine concentrations remained within the therapeutic range throughout the trial. Thirteen patients completed the study. In partial epilepsy of 7 the seizure frequency was reduced by 27% during valproate (p less than 0.05), compared with placebo, while no improvement was found during taltrimide. In 6 with primary generalized epilepsy, the number of seizures was reduced by 49% during taltrimide and by 38% during valproate, but neither effect was significant, compared with placebo. Headache was reported by 3 patients while on taltrimide. One with hypersensitivity history developed petecchiae and nasal bleeding during taltrimide and, therefore, the treatment was stopped. The three other interruptions were independent of taltrimide. Thus, the only statistically significant effect in this study was that of valproate in partial epilepsy.     

Idiopathic generalized epilepsy presenting with hemiconvulsive seizures

PURPOSE: Unilateral seizures, or hemiconvulsive attacks, are motor seizures with tonic and/or clonic phenomena that involve only one side of the body. METHODS: We describe three adolescents who presented with hemiconvulsive seizures and were found to have 3-cps generalized spike-and-wave discharges on ictal and/or interictal EEG. All had normal neuroimaging studies. Two patients had been previously treated with carbamazepine, which led to a partial response in one patient. RESULTS: All three patients, however, are now seizure free on either sodium valproate or a combination of sodium valproate and lamotrigine. We believe the electroclinical diagnosis is that of idiopathic generalized epilepsy. CONCLUSIONS: Idiopathic generalized epilepsy presenting with hemiconvulsive seizures has not, to our knowledge, been previously described. However, the correct diagnosis of an idiopathic generalized seizure disorder, as opposed to a partial seizure disorder, has important treatment implications. The possible mechanism of hemiconvulsive seizures in idiopathic generalized epilepsy is discussed.     

Double-blind substitution of vigabatrin and valproate in carbamazepine-resistant partial epilepsy. 012 Study group

Patients from 12 countries reporting two or more partial seizures per month despite treatment with optimal doses of CBZ were randomised to additional vigabatrin (VGB, 2-4 g daily) or sodium valproate (VPA, 1-2 g daily) using a double-blind, double-dummy design. The study included a 6 month retrospective baseline on unchanged CBZ dosage, a month's prospective baseline, a short titration phase, and an assessment period lasting 3 months on duotherapy. CBZ was withdrawn over a further 2 months in responders ( > or = 50% monthly seizure reduction compared with baseline), who continued on alternative monotherapy for 3 or more months. If seizure control deteriorated, CBZ was reinstated and these patients were also followed up for 3 months. A total of 215 patients (108 VGB, 107 VPA) reporting a mean of seven partial seizures per month fulfilled the criteria for the intention-to-treat analysis. 53 and 51% of patients in the VGB and VPA group respectively achieved a monthly reduction in seizure numbers > or = 50%, respectively. 27 and 31% maintained alternative monotherapy. Overall, 17% (7% monotherapy, 10% duotherapy) of the VGB treated patients and 19% (8% monotherapy, 11% duotherapy) of the VPA group remained seizure-free during the final 3 month treatment period. VGB and VPA, which increase neuronal inhibition mediated by gamma aminobutyric acid, can be added to or substituted for CBZ when this Na+ channel blocker fails to control partial seizures. This lends credence to the hypothesis in support of a mechanistic approach to the management of epilepsy.     

Timed pentylenetetrazol infusion test: a comparative analysis with s.c.PTZ and MES models of anticonvulsant screening in mice.

The intravenous pentylenetetrazol (i.v.PTZ) seizure test provides threshold dose for induction of seizures in individual animals. In the present study, the i.v. and s.c.PTZ seizure models in mice were compared for seizure pattern, intra- and interanimal variability. Anticonvulsant activities of several antiepileptic drugs (AEDs) at non-ataxic dose levels were evaluated in the PTZ and maximal electroshock (MES) seizure tests. In the i.v.PTZ test, at 0.5 ml/min rate of administration, the mean threshold PTZ doses for induction of clonus and tonic extensor were 44.17 and 99.59 mg/kg, respectively. The intra- and interanimal variabilities in the seizure response were low in the i.v.PTZ as compared to the s.c.PTZ model. Phenobarbital sodium, ethosuximide, sodium valproate, diazepam, tiagabine, oxcarbazepine and zonisamide enhanced threshold or onset latency for clonus in the i.v. and s.c.PTZ tests, respectively. Levetiracetam and pregabalin were active in the i.v.PTZ test, but had no effect in the s.c.PTZ test. Ability of AEDs to protect from tonic extensor was compared in the MES and i.v.PTZ tests. For this effect, phenobarbital sodium, phenytoin, carbamazepine, sodium valproate, gabapentin, oxcarbazepine, zonisamide and pregabalin were effective in the i.v.PTZ and MES tests. Ethosuximide, diazepam and levetiracetam were effective in the i.v.PTZ test, but not the MES test. On the contrary, lamotrigine and topiramate were active in the MES, but not the i.v.PTZ test. These results indicate that it is advantageous to use i.v.PTZ test as an acute seizure model for screening of antiepileptic drugs. This model can identify molecules with varied mechanism of action and broad clinical utility in the treatment of epilepsy.     

Efficacy and tolerability of conversion to monotherapy with lamotrigine compared with valproate and carbamazepine in patients with epilepsy

OBJECTIVE: This randomized, open-label study was designed to compare the efficacy and tolerability of lamotrigine monotherapy with those of valproate and carbamazepine monotherapy in patients with epilepsy whose seizures were uncontrolled on their prestudy antiepileptic drug monotherapy. METHODS: Patients meeting eligibility criteria were randomized 2:1 to lamotrigine:carbamazepine or lamotrigine:valproate. The treatment phase was divided into a 4-week dose-escalation phase (Weeks 1-4), during which lamotrigine, carbamazepine, or valproate was added to patient's prestudy monotherapy; an 8-week add-on phase (Weeks 5-12), during which patients were stabilized on both the study medication and their prestudy antiepileptic therapy; an 8-week withdrawal phase (Weeks 13-20), during which prestudy antiepileptic therapy could be withdrawn if clinically appropriate; and an 8-week monotherapy phase (Weeks 21-28), during which patients could be treated with study medication as monotherapy. RESULTS: The numbers of patients randomized to the carbamazepine and valproate arms of the study were 144 (98 lamotrigine, 46 carbamazepine) and 158 (105 lamotrigine, 53 valproate), respectively. Successful monotherapy sustained for at least 7 weeks was achieved in comparable percentages of patients in the lamotrigine group (56%) and the carbamazepine group (54%) and in more patients in the lamotrigine group (49%) than the valproate group (40%). Among monotherapy completers, the percentage of patients with zero seizures during the monotherapy phase was comparable for lamotrigine (41%) and carbamazepine (30%) and significantly higher (P<0.05) with lamotrigine (32%) than with valproate (11%). No differences between treatments were observed with respect to time to treatment failure or time to first seizure. Lamotrigine was also better tolerated than carbamazepine or valproate. CONCLUSION: Lamotrigine monotherapy was as effective as and better tolerated than carbamazepine or valproate monotherapy in patients whose seizures were uncontrolled on their prestudy antiepileptic drug monotherapy.     

Epileptic negative myoclonus induced by carbamazepine in a child with BECTS. Benign childhood epilepsy with centrotemporal spikes.

A 7-year-old female with benign childhood epilepsy with centrotemporal spikes developed epileptic negative myoclonus (ENM) seizures during carbamazepine (CBZ) treatment. She had experienced nocturnal partial seizures since 5 years of age. Interictal electroencephalography demonstrated typical rolandic discharges. Valproate was first initiated at 6 years of age, but the seizures were uncontrollable. Carbamazepine was added and valproate withdrawn. The frequency of partial seizures did not decrease. Moreover, she had brief episodes of tone loss in each or both arms and eye blinking several weeks after CBZ introduction. Unilateral loss of arm tone corresponded to spike-and-wave discharges in the contralateral centrotemporal region, and a loss of tone in arms was associated with bilateral synchronous discharges. Eye blinking was also related to bilateral synchronous discharges and classified as a myoclonic seizure. The ENM and myoclonic seizures disappeared soon after CBZ withdrawal. Therefore the authors concluded that CBZ induced the ENM and myoclonic seizures in this patient. CBZ sometimes induces generalized seizures in the treatment of partial epilepsy and generalized epilepsy. CBZ-induced ENM seizures should be considered when a brief lapse of tone appears during CBZ treatment.     

The dynamics of drug treatment in epilepsy: an observational study in an unselected population based cohort with newly diagnosed epilepsy followed up prospectively over 11-14 years

OBJECTIVES: To study prospectively long term dynamics and patterns of treatment in a population based cohort of patients with newly diagnosed epilepsy. METHODS: 564 patients with definite epilepsy entered the UK National General Practice Study of Epilepsy (NGPSE), between 1984 and 1987, and were prospectively followed up for between 11-14 years. RESULTS: Treatment was started in 433 (77%) patients. Only 15% of single seizure patients had medication prescribed initially, although due to high seizure recurrence, more than 70% ultimately received antiepileptic medication. 209/564 patients (37%) were on drug therapy for epilepsy at the time of last follow up. 168/564 patients (30%) have stayed continuously on medication and another 41/564 patients (7%) restarted drug therapy because of seizure recurrence, having withdrawn medication. 98/209 (47%) of those on treatment are known to be in 5 year terminal remission. Phenytoin (29%) and carbamazepine (27%) were the most commonly preferred first line drugs followed by valproate (15%). Less than half of treated patients with partial seizures received carbamazepine as a first line drug and less than a third with generalised seizures were prescribed valproate as first choice drug. Nine out of 31 (29%) patients with one or more seizures a week at last follow up had never tried a second drug and only seven (23%) had tried four or more drugs. 11% of all treatment changes involved a new antiepileptic drug. Treatment changes were associated with low terminal remission rates. CONCLUSIONS: Out of 30 000 patients with newly diagnosed epilepsy every year in the United Kingdom, about 6000 have inadequate seizure control in the long term. About a third of the patients in this group have one or more seizures every month. Only two thirds of these patients with frequent seizures are likely to switch medication to try and achieve better seizure control. There is probably still considerable room for improvement in prescribing practice in the United Kingdom.     

Barbiturate-refractory epilepsy: safe schedule for therapeutic substitution

Barbiturates are considered first line antiepileptic drugs in third world countries due to traditional and economic reasons. This prospective uncontrolled study of 52 patients aged 15 to 64 years (mean 24) demonstrates that patients who become refractory to barbiturates are mainly those with partial seizures with or without generalization or with a focal EEG abnormality (71%). Seizures tend to become refractory approximately 6 years after barbiturates were started. Progressive barbiturate withdrawal over a period of two to 8 months (mean 5) with institution of treatment with carbamazepine, phenytoin or sodium valproate allowed complete barbiturate withdrawal in 42 of the 52 patients (81%). Furthermore monthly seizure frequency in those in whom barbiturates were withdrawn decreased from 7.1 to 1.7 per patient. An improvement in mental status was observed but not measured. These results show that barbiturates should not be first-choice drugs in patients who have a chronic disease such as epilepsy, and indicate a schedule for barbiturate withdrawal which is safe and independent of hospitalization or monitoring of antiepileptic drug serum concentrations.     

A Retrospective Study of 113 Epileptic Patients Treated with Sustained-Release Valproate

Summary: A retrospective study of 113 patients treated with a sustained-release form of valproate (SRF-VPA), known as the "chrono" formulation in most European countries, led to the following conclusions: Patients treated with the old VPA formulation could immediately receive the same daily dosage of SRF-VPA without loss of seizure control when administered as a single evening dose. The tolerability of SRF-VPA was good and twice or single daily dosing was preferred by all our patients. Whether or not SRF-VPA should be used as first or second-line treatment in partial seizures that do or do not secondarily generalize is unclear. Our study demonstrates that the efficacy of SRF-VPA is comparable with that of other major antiepileptic drugs such as carbamazepine (CBZ). In refractory seizures, the combination of SRF-VPA and CBZ seemed to be the most satisfactory treatment. Based on these results SRF-VPA is a promising drug for all types of seizures even in low daily dosage, but further clinical work is required to confirm our observations.     

Open study evaluating lamotrigine efficacy and safety in add-on treatment and consecutive monotherapy in patients with carbamazepine- or valproate-resistant epilepsy.

Lamotrigine is a broad-spectrum antiepileptic drug that blocks sodium channels, thereby inhibiting the pre-synaptic release of excitatory neurotransmitters. The primary aim of the study was to evaluate lamotrigine add-on therapy and consecutive monotherapy in patients with epilepsy whose seizures were not controlled by carbamazepine or valproate. One hundred and twenty six epilepsy patients at 18 centres in Poland were recruited into a lamotrigine substitution study. In all patients, existing seizures were poorly controlled with valproate (n= 63) or carbamazepine (n= 63) monotherapy. The study consisted of four phases: (1) a 4-week lamotrigine dose-escalation phase, (2) an 8-week lamotrigine add-on phase, (3) an 8-week carbamazepine/valproate withdrawal phase, and (4) an 8-week lamotrigine monotherapy phase. Of 126 patients recruited into the study, 107 (85%) completed dose-escalation and add-on therapy with lamotrigine and 85 (68%) completed lamotrigine monotherapy. Fifty percent of patients during add-on therapy and 53% during lamotrigine monotherapy experienced at least 50% reduction in total seizures (responders) compared to the pre-study period. Approximately 20% of patients during add-on therapy and 27% during lamotrigine monotherapy were seizure free. Total well-being was assessed using a Visual Analogue Scale with 62% of patients during add-on therapy and 60% in lamotrigine monotherapy reporting improvement in scores. Lamotrigine was generally well tolerated. Treatment was discontinued in 7% because of adverse events. In conclusion, lamotrigine is an effective AED in add-on therapy and monotherapy, it is safe and well tolerated, and successful conversion from add-on to monotherapy can be achieved in many cases. An additive effect between lamotrigine and valproate was observed.