Antidepressant effects of lamotrigine in rapid cycling bipolar disorder

Rapid cycling bipolar disorder: Literature review on pharmacological treatment illustrated by a case report on ketamine

INTRODUCTION

Rapid cycling bipolar disorder (RCBD) is defined as four or more affective episodes (depression, mania or hypomania) within 1 year. RCBD has a high point of prevalence (from 10% to 20% among clinical bipolar samples) and is associated with greater severity, longer illness duration, worse global functioning and higher suicidal risk, but there is no consensus on treatment option. The use of several pharmacological agents has been reported (levothyroxine, antipsychotics, antidepressants and mood stabilizers).

OBJECTIVE

The main objective of this review was to propose a critical review of the literature and to rank the pharmacological agent using a level of evidence (LEO) adapted from the Center for Evidence-Based Medicine, and to illustrate it with a case report on off-label intravenous ketamine.

METHOD

We conducted a review using the MeSH terms and keywords (bipolar [Title/Abstract]) AND (rapid [Title/Abstract]) AND (cycling [Title/Abstract]) AND (treatment [Title/Abstract]). Alexis Bourla and Stéphane Mouchabac screened 638 documents identified through literature search in Medline (PubMed) or by bibliographic references and 164 abstracts were then analyzed. Nonpharmacological treatments were excluded.

RESULT

Seventy articles were included in the review and divided into six categories: mood stabilizers, antipsychotics, hormonal treatments, ketamine and other pharmacological treatments.

DISCUSSION

Our review highlights the heterogeneity of the pharmacological treatment of RCBD and no clear consensus can emerge.

Lamotrigine in bipolar affective disorder

Aims and method

The study aimed to assess the available data on the use of lamotrigine as a mood stabilising agent. We reviewed all published and unpublished data available to us through a Medline search from 1987–1998 and from our own files, which include reference materials presented at conferences as well as published reports.

Results

Most of the data found were derived from case reports or open trials. We could find no published double-blind, placebo-controlled studies. The data from initial open trials suggest that lamotrigine may be effective in bipolar disorder, but futher data are required before specific treatment recommendations can be made.

Clinical implications

At this early stage, there are too few data to recommend lamotrigine for first or second line therapy in bipolar disorder. However, initial reports are very promising and this agent may eventually be unequivocally shown to be useful in treating mania, hypomania, depression, rapid cycling and mixed affective states in people with bipolar disorder.

Circadian Gene Circuitry Predicts Hyperactive Behavior in a Mood Disorder Mouse Model

Bipolar disorder, also known as manic-depressive illness, causes swings in mood and activity levels at irregular intervals. Such changes are difficult to predict, and their molecular basis remains unknown. Here, we use infradian (longer than a day) cyclic activity levels in αCaMKII (Camk2a) mutant mice as a proxy for such mood-associated changes. We report that gene-expression patterns in the hippocampal dentate gyrus could retrospectively predict whether the mice were in a state of high or low locomotor activity (LA). Expression of a subset of circadian genes, as well as levels of cAMP and pCREB, possible upstream regulators of circadian genes, were correlated with LA states, suggesting that the intrinsic molecular circuitry changes concomitant with infradian oscillatory LA. Taken together, these findings shed light onto the molecular basis of how irregular biological rhythms and behavior are controlled by the brain.

The 'disconnect' between initial judgments of lamotrigine vs. its real-world effectiveness in managing bipolar disorder. A tale with wider ramifications

OBJECTIVE

To detail the disconnect between the quantified efficacy of the mood stabilizer lamotrigine in its registration controlled trials and its later judged clinical effectiveness and consider some determinants of disconnects between some efficacy trial findings and 'real-world' clinical effectiveness judgments.

METHOD

Published articles considering lamotrigine as a treatment for the bipolar I or II disorders were selected for review. While randomized controlled trials were weighted, we also consider open trials and effectiveness observations from clinician researchers and demonstrate that lamotrigine has been quite variably judged over time.

RESULTS

We suggest that the early trials evaluating lamotrigine for acute bipolar disorder depression focused on a suboptimal clinical target, and in so doing, ensured less lamotrigine efficacy compared with trials of bipolar disorder preventative treatment. Moreover, a number of additional methodological limitations compromised analyses. We also detail variable reporting of actual study results. The initial sharp disconnect (between efficacy and effectiveness judgments) has narrowed as lamotrigine has been evaluated and progressively taken up as a maintenance mood stabilizer.

CONCLUSION

The lamotrigine disconnect story provides a number of salutary lessons that are salient to evaluating the effectiveness and ecological niche of any psychotropic medication. The lamotrigine story presented here argues strongly for the wisdom of encouraging an iterative process between efficacy studies and clinical observation.

Lamotrigine reverses masseter overactivity caused by stress maybe via Glu suppression

Experimental and non-experimental stress significantly increase masseter muscle tone, which has been linked to the symptoms and pathogenesis of several stomatognathic system diseases. Until now, the mechanism underlying this phenomenon has remained unclear. The current study was performed to determine the mechanism of the stress-induced increase in masseter muscle tone and to investigate the effect of lamotrigine on this change. Animals challenged by repeated restraint stress received either saline as a vehicle or lamotrigine in doses of 20, 30 or 40 mg/kg body weight, whereas control animals received saline without stress treatment. Masseter muscle tone was assessed using electromyography. The activity of glutamate-related metabolic enzymes (glutaminase and glutamine synthetase) in the trigeminal motor nucleus was also investigated. Our results showed an interesting phenomenon: masseter muscle activity increased concurrently with the upregulation of the glutamate concentration after stress treatment. The activities of glutaminase and glutamine synthetase in the trigeminal motor nucleus were also upregulated and downregulated, respectively, when the rats were challenged by prolonged stress. The animals treated with lamotrigine at moderate and high doses had significantly decreased masseter muscle tone compared with stressed animals treated with vehicle. These results suggested that increased glutaminase activity and decreased glutamine synthetase activity increased glutamate production and decreased glutamate decomposition, causing an increase in glutamate levels in the trigeminal motor nucleus and eventually increasing masseter muscle tone. The administration of lamotrigine at doses of 30 or 40 mg/kg body weight effectively mitigated the adverse effects of stress on masseter muscle tone via inhibition of glutamate release.

Lamotrigine in epilepsy, pregnancy and psychiatry--a drug for all seasons?

Lamotrigine has been demonstrated to be effective as both an antiepileptic drug and a mood stabiliser. For epilepsy it is less efficacious than valproate in primary generalised epilepsy, but it is comparable to some traditional drugs in partial epilepsy. In psychiatry it has significant advantages over other mood stabilisers for the treatment and prevention of depressive phases of bipolar illness, but not for the treatment of mania. It has a more benign adverse effect profile than older antiepileptic agents and is not a proven teratogen. Risk of adverse reactions is reduced by commencing treatment at a markedly reduced dose that is gradually increased.

Anticonvulsant drugs in bipolar disorder

Although much progress has been made in successfully treating bipolar disorder, there is increasing awareness of the limitations of traditional treatment regimens such as lithium and neuroleptics. The large family of anticonvulsant drugs, however, appears to be capable of providing new treatment options, not only as medication of second choice in patients refractory to treatment, but often as a treatment standard with high efficacy and low incidence of side effects. Besides established mood stabilizers such as carbamazepine and valproate, new antiepileptic drugs are entering the field with promising initial results in the treatment of bipolar patients. Furthermore, bringing to light the mechanisms of action of anticonvulsants and the similarities between anticonvulsants effective in bipolar disorder may also deepen our understanding of the pathophysiological basis of the disorder.

The psychopharmacology of aggressive behavior: a translational approach: part 2: clinical studies using atypical antipsychotics, anticonvulsants, and lithium

Patients experiencing mental disorders are at an elevated risk for developing aggressive behavior. In the past 10 years, the psychopharmacological treatment of aggression has changed dramatically owing to the introduction of atypical antipsychotics on the market and the increased use of anticonvulsants and lithium in the treatment of aggressive patients.This review (second of 2 parts) uses a translational medicine approach to examine the neurobiology of aggression, discussing the major neurotransmitter systems implicated in its pathogenesis (serotonin, glutamate, norepinephrine, dopamine, and γ-aminobutyric acid) and the neuropharmacological rationale for using atypical antipsychotics, anticonvulsants, and lithium in the therapeutics of aggressive behavior. A critical review of all clinical trials using atypical antipsychotics (aripiprazole, clozapine, loxapine, olanzapine, quetiapine, risperidone, ziprasidone, and amisulpride), anticonvulsants (topiramate, valproate, lamotrigine, and gabapentin), and lithium are presented. Given the complex, multifaceted nature of aggression, a multifunctional combined therapy, targeting different receptors, seems to be the best strategy for treating aggressive behavior. This therapeutic strategy is supported by translational studies and a few human studies, even if additional randomized, double-blind, clinical trials are needed to confirm the clinical efficacy of this framework.

Efficacy and safety of two treatment algorithms in bipolar depression consisting of a combination of lithium, lamotrigine or placebo and paroxetine

OBJECTIVE

In a previous paper, we reported about the efficacy of the addition of lamotrigine to lithium in patients with bipolar depression. In the second phase of this study paroxetine was added to ongoing treatment in non-responders.

METHOD

Bipolar depressed patients (n = 124) treated with lithium were randomized to addition of lamotrigine or placebo. In non-responders after 8 weeks, paroxetine 20 mg was added for another 8 weeks to ongoing treatment.

RESULTS

After 8 weeks the improvement in patients treated with lamotrigine vs. patients treated with placebo was significant. After addition of paroxetine this difference disappeared as a result of greater further improvement in the non-responders to placebo.

CONCLUSION

Addition of lamotrigine to lithium was found effective in bipolar depressed patients. Further addition of paroxetine in non-responders to lithium plus lamotrigine did not appear to provide additional benefit, while it appeared to do so in non-responders to lithium plus placebo.

Sustained remission with lamotrigine augmentation or monotherapy in female resistant depressives with mixed cyclothymic-dysthymic temperament

BACKGROUND

The treatment of bipolar depression remains problematic. Lamotrigine has been shown in randomized controlled studies to be efficacious in preventing bipolar depression and rapid cycling states.

METHODS

Twenty-four women with cyclothymic temperament and refractory depression were recruited from four outpatient sites (three primary care and one psychiatric) and treated with lamotrigine in a naturalistic, open-label study. Temperament was determined by responses on the TEMP-A self-rating scale. Eighteen (75%) of these cyclothymic patients also scored high on the depressive temperament. Eighteen (75%) met DSM-IV criteria for bipolar II disorder. In two thirds of the cases, lamotrigine was add-on therapy to an antidepressant. Response to therapy was assessed using the DSM-IV Global Assessment of Functioning (GAF).

LIMITATIONS

This study was naturalistic in design, without controls or blinds.

RESULTS

Of the 23 patients who remained in the study, 16 (70%) had significant, sustained responses. Of these 16, 12 (75% of responders, 52% of the total) had remissions (GAF > 80) sustained longer than 12 months. Robust, sustained responses to lamotrigine monotherapy were seen in 4 patients (17%). Seven patients (30%) received no apparent benefit from lamotrigine.

CONCLUSIONS

Lamotrigine induced prolonged illness remissions in a substantial number of female patients whose symptoms were both complex and refractory. Most manifested high scores on the cyclothymic and depressive temperaments, and prior refractoriness to multiple antidepressant and antidepressant/mood stabilizer combinations, before remitting with lamotrigine augmentation or monotherapy.

Somatic treatment of bipolar disorder in children and adolescents

The currently available data from randomized, controlled trials and a considerable amount of open clinical data suggest that adolescent-onset bipolar disorder probably responds to the same agents as adult-onset bipolar disorder. Research examining psychopharmacologic treatment approaches in the early-onset bipolar disorder is limited, however. Methodologic problems include small sample sizes, lack of comparison groups, retrospective designs,and lack of standardized measures. In addition, sometimes no clear differentiation is made between mania and bipolar disorder, the latter term being used broadly in the literature. Often the studies show that symptoms improve because of treatment, but the functioning of the patients does not improve significantly. More research is clearly needed in all aspects of this disorder but especially in examining the efficacy of various types of treatment, its longitudinal course, and diagnostic issues. The indications for, and the overall duration of, long-term maintenance therapy need further study.Many adolescents and children with bipolar disorder do not respond to any of the first-line pharmacologic treatments; therefore, studies with novel agents should be extended to patients in this age range. Furthermore, physicians will probably continue to use combination therapies when confronted by either lack of efficacy or delayed onset of efficacy with a single agent. Thus, such resultant drug-drug interactions also should also be systematically studied [97].

Lamotrigine use in geriatric patients with bipolar depression

OBJECTIVE

To study the effectiveness of adding lamotrigine to the treatment of inpatient geriatric patients with bipolar disorder (BD) who were in the depressed phase and had been on lithium and valproate for at least 3 months.

METHOD

Lamotrigine was started at 25 mg given at bedtime, with weekly incremental increases of 12.5 mg daily until a total dosage of either 75 mg or 100 mg was obtained. Improvement was measured by clinical interview and Hamilton Depression Rating Scale (HDRS) scores. Patients were reassessed at 6 weeks, and if their HDRS score had decreased by at least 50%, they were considered to have improved.

RESULTS

The study group comprised 5 women with an average age of 71.5 years (range 65 to 85). Four had rapid-cycling BD, and 1 had mixed BD. All patients had early age of onset, as judged by their first contact with a psychiatrist or their first hospitalization. The average initial HDRS score was 27 (range 20 to 35). Of the patients, 3 out of the 5 had remission of symptoms, as judged by clinical interview and reduction of their HDRS score by 50%. At 3 months follow-up, these 3 patients had not required rehospitalization and were doing well. Lamotrigine was well tolerated, and none of the patients developed a rash. One patient did develop coarse hand tremor that improved when the lamotrigine dosage was decreased.

CONCLUSIONS

Lamotrigine in conjunction with lithium and valproate may be effective in treating geriatric patients with BD and depression.

Lamotrigine monotherapy improves health-related quality of life in epilepsy: a double-blind comparison with valproate

The effects of monotherapy with lamotrigine on health-related quality of life were compared with those of valproate monotherapy in a randomized, double-blind trial designed to evaluate treatment-emergent weight changes in patients with epilepsy. At the end of 8 months of treatment, significantly more patients using lamotrigine compared with valproate experienced quality-of-life improvements on the Health Perceptions (42% vs 15%), Energy/Fatigue (47% vs 28%), and Social Isolation (35% vs 16%) subscales of the Quality of Life in Epilepsy-89 (QOLIE-89) questionnaire (P<0.05). Compared with valproate-treated patients, lamotrigine-treated patients were four times more likely to experience improvement in Health Perceptions, 2.3 times more likely to experience improvement in Energy/Fatigue, and 2.8 times more likely to experience improvement in Social Isolation (P<0.05). These quality-of-life improvements are consistent with the improvements in mood measured with the Beck Depression Inventory, the Cornell Dysthymia Rating Scale, and the Profile of Mood States among patients receiving lamotrigine. These data show that lamotrigine monotherapy provides benefits over valproate monotherapy in improving several aspects of health-related quality of life in patients with epilepsy. The observation that quality-of-life improvements during lamotrigine monotherapy occurred concurrently with improvements in mood suggests that the quality-of-life and mood changes may be causally related.

Lamotrigine update and its use in mood disorders

OBJECTIVE

To provide a qualitative, systematic update and review of the pharmacology, pharmacokinetics, efficacy in mood disorders, adverse effects, and costs of lamotrigine.

DATA SOURCES

Citations obtained from MEDLINE searches (1985-September 2001) using lamotrigine as a text word, articles identified in reference lists of pertinent articles, abstracts presented at conferences, and research data from GlaxoSmithKline.

DATA EXTRACTION

English-language articles were considered for possible inclusion. Each title and abstract was examined to determine whether the publication contained up-to-date information relevant to the objective. Twenty clinical trials that provided data on response rates in mood disorders were tabulated.

DATA SYNTHESIS

Lamotrigine's primary action is to modulate voltage-gated sodium channels. Evidence suggests that it decreases glutamate transmission, directly reduces calcium influx, mildly blocks transmitter reuptake, and alters intracellular mechanisms of resting transmitter release. The average half-life of lamotrigine is approximately 24 hours, but decreases to approximately 7.4 hours when used concurrently with phenytoin, and increases to approximately 59 hours with valproic acid. Seven of the 20 clinical trials were randomized, double-blind, and controlled. Existing data are inadequate to evaluate lamotrigine use in major depression. The pooled response rates for patients with depressed, manic, mixed, and rapid cycling bipolar disorder were similar, ranging from 52% to 63%. Adverse effects are infrequent when the drug is used alone, but become more frequent when lamotrigine is combined with other anticonvulsants. While most rashes are mild, approximately 1 in 500 patients develops exfoliative dermatitis. A slow upward dose titration is recommended to reduce the incidence of serious rash, but this may delay the attainment of adequate dosage for 6 weeks. Lamotrigine has positive effects on cognitive function, but occasionally produces insomnia. Lamotrigine costs 2-4 times more than lithium, carbamazepine, and generic valproic acid.

CONCLUSIONS

When efficacy, adverse effects, and cost are considered, lamotrigine should probably be reserved as a second-line agent for bipolar depression.

Clinical predictors of response to lamotrigine and gabapentin monotherapy in refractory affective disorders

BACKGROUND

The objective of the current study was to examine possible clinical predictors of positive response to lamotrigine or gabapentin monotherapy in treatment-refractory affectively ill patients.

METHODS

Forty-five patients with treatment refractory bipolar (n = 35) or unipolar (n = 10) affective disorder participated in a clinical study evaluating six weeks of treatment with lamotrigine, gabapentin, or placebo monotherapy given in a double-blind, randomized fashion with two subsequent cross-overs to the other agents. Patients received daily mood ratings and weekly cross-sectional scales. Much or very much improved on the Clinical Global Impression scale modified for bipolar illness was considered a positive response. Degree of response was correlated with a number of baseline demographic and course of illness variables in a univariate analysis and then by linear regression.

RESULTS

Response rates to lamotrigine (51%) exceeded those to gabapentin (28%) and placebo (21%). A positive response to lamotrigine monotherapy was associated with a bipolar diagnosis; fewer hospitalizations; fewer prior medication trials; and male gender (of which the latter two variables survived logistic regression). For gabapentin, degree of response correlated with shorter duration of illness; younger age; and lower baseline weight (with the latter two surviving linear regression).

CONCLUSIONS

In this highly treatment-refractory population, lamotrigine appeared most effective for male patients with fewer prior medication trials. Gabapentin monotherapy, although not better than placebo, appeared most effective in those with younger age and lower baseline weight. These preliminary data in a treatment refractory subgroup may help in the further definition of the range of clinical utility of these widely used anticonvulsants.

Lamotrigine: a review of clinical studies in bipolar disorders

OBJECTIVE

This article reviews published studies on the use of lamotrigine in the treatment of bipolar disorder (BD).

METHOD

We performed a Medline search to identify the literature data base available on double-blind, open-label studies and case series on the use of lamotrigine to treat BD.

RESULTS

Three double-blind studies, 3 open-label studies, and 2 case series have been conducted to date (n = 401 patients). Most patients were either nonresponders or partial responders to other mood stabilizers. Overall, 50% to 83% of the patients responded to lamotrigine; doses in the studies ranged from 50 to 400 mg daily. Switching to mania while on 200 mg of lamotrigine or more was extremely rare, and there were no reports of serious adverse effects during the study periods.

CONCLUSION

Lamotrigine is proving to be an effective agent in the treatment of BD and may be useful for patients who have not responded to other mood stabilizers.

Lamotrigine Monotherapy Improves Depressive Symptoms in Epilepsy: A Double-Blind Comparison with Valproate

Depressive symptoms are highly prevalent in patients with epilepsy. The antiepileptic drug lamotrigine has been shown to be an effective treatment for the depressive phase of bipolar disorder and to enhance mood and well-being in epilepsy patients. The effects of lamotrigine monotherapy on depressive symptoms in epilepsy have not been evaluated to date in a controlled clinical trial. A recently completed double-blind epilepsy trial comparing the effects of lamotrigine monotherapy and valproate monotherapy on weight change incorporated a battery of standard mood assessments. Mean screening Beck Depression Inventory scores showed that both lamotrigine and valproate groups suffered from mild depression at baseline. Lamotrigine monotherapy was reliably associated with earlier and larger improvements than valproate in mood assessed with the Beck Depression Inventory, the Cornell Dysthymia Rating Scale, and the Profile of Mood States. Considered in the context of other data showing lamotrigine's antidepressant efficacy in bipolar depression, these results suggest that lamotrigine improves mood in mildly depressed patients with epilepsy. Lamotrigine may be particularly useful in treating epilepsy patients with comorbid depression, the most common psychiatric illness in epilepsy.

Tolerance to the anticonvulsant effects of lamotrigine on amygdala kindled seizures: cross-tolerance to carbamazepine but not valproate or diazepam

Using an amygdala-kindled seizure paradigm, we evaluated the acute and chronic anticonvulsant effects of lamotrigine (LTG). Lamotrigine produced dose-dependent inhibitory effects on seizure stage, afterdischarge (AD), and seizure duration. Lamotrigine (15 mg/kg) also increased the afterdischarge and seizure thresholds. Following repeated LTG administration and stimulation at 48-h intervals, tolerance developed to LTG's (15 mg/kg) anticonvulsant effects, and cross-tolerance was observed to the anticonvulsant effects of carbamazepine (CBZ, 15 mg/kg). In a separate group of kindled rats, CBZ (15 mg/kg) was repeatedly administered to induce tolerance. This led to a partial cross-tolerance to LTG, manifesting as an increased rate of tolerance development to LTG, and seizures following the first injection in some animals, which were not observed in CBZ-nontolerant controls. When these rats were made fully tolerant to LTG and then exposed to higher doses of LTG (30 and 50 mg/kg), no anticonvulsant effects were observed. In contrast, higher doses of CBZ (30 mg/kg) did restore efficacy in CBZ-tolerant animals. Cross-tolerance from LTG to valproate and diazepam was not observed, although cross-tolerance from CBZ to valproate has been reported previously. These data suggest that LTG has both shared and distinct anticonvulsant mechanisms from those of CBZ on amygdala-kindled seizures. The implications of these results for clinical therapeutics remain to be evaluated.

Lamotrigine for the treatment of bipolar disorder

OBJECTIVE

To describe the available data regarding the clinical efficacy of lamotrigine for the treatment of bipolar disorder.

SUMMARY

Anticonvulsants have emerged as alternative mood-stabilizing agents for patients with bipolar disorder who do not respond to lithium. Data regarding the efficacy of lamotrigine have been generated primarily from case reports, small open trials, and one large, randomized, placebo-controlled trial. These reports suggest that lamotrigine may be effective for the management of bipolar disorder.

CONCLUSIONS

Although current data are limited, treatment-refractory patients with bipolar disorder may benefit from lamotrigine therapy. Several studies are currently underway to determine the appropriate role of lamotrigine in the treatment of bipolar disorder.

Bipolarity in children

Childhood and adolescent bipolar disorder have been less studied than adult onset bipolar illness. However, case reports of mania in childhood can be found as early as the mid 19th century. Historically, several factors have made the accurate diagnosis of bipolar disorder in childhood difficult: clinical bias against the diagnosis of mania in children; low base rate of disorder; symptom overlap between bipolar disorder and other more prevalent childhood-onset psychiatric disorders; and developmental constraints and variability in clinical presentation. The epidemiology of juvenile-onset bipolar disorder remains an open topic for research. The disorder appears to increase in prevalence with advancing age until young adulthood. Reported phenomenology of bipolar disorder in children and adolescents indicates a highly variable presentation with a developmental trend towards increased resemblance to the adult phenotype with increasing age of onset. Diagnostic accuracy for the disorder is improved by adherence to diagnostic and statistical manual of mental disorders (DSM) criteria and may be aided by structured or semistructured diagnostic interviews. The course of bipolar disorder in children and adolescents has also received limited systematic study. However, research to date supports a clinical picture of a relapsing, recurrent illness with substantial morbidity. Systematic studies of pharmacologic treatments of acute mania in children and adolescents are limited in number and scope. Clinical justification for the use of acute antimanic treatments such as lithium and valproic acid is still based upon studies conducted in adults. There remains an immediate and significant need for additional research into all aspects of juvenile-onset bipolar disorder.

Mania in the geriatric patient population: a review of the literature

The diagnosis of mania in the geriatric population is uncommon. However, it comprises significant healthcare utilization and cost requirements, which are expected to increase in the near future with the projected increase in the geriatric population. The authors review literature pertaining to geriatric mania and discuss epidemiology, psychopathology, neuropathology, differential diagnosis, evaluation, treatment, and outcomes. Literature searches were performed by GratefulMed for the years 1960-1997, with secondary- and tertiary-source follow-up. It is clear from this review that geriatric mania is a complex illness with many possible etiologies and treatments. Much more research needs to be conducted in all of the areas reviewed.

Lamotrigine in the treatment of bipolar depression

Several case reports and open studies have reported the efficacy of lamotrigine in bipolar depression. A randomised placebo-controlled 7-week study comparing two doses of lamotrigine with placebo in 195 patients with moderate to severe bipolar depression has now been completed. Lamotrigine was superior to placebo after 3 weeks as assessed by changes in the Montgomery-Asberg Depression Rating Scale (MADRS). A response, defined as more than 50% improvement on the MADRS occurred in 56 and 48% of the lamotrigine 200 and 50 mg/day groups, respectively, compared with 29% for placebo (P<0.05). There was no evidence that lamotrigine destabilised mood or precipitated mania. Tolerability was good and there were no cases of serious rashes. Preliminary results from an ongoing study also indicate that lamotrigine is more effective than gabapentin in bipolar depression. In conclusion, lamotrigine is effective in alleviating bipolar depression, without causing mood destabilisation. Slow dosage escalation yields good tolerability.

Spectrum of activity of lamotrigine in treatment-refractory bipolar disorder

OBJECTIVE

New mood stabilizers are needed that possess efficacy for all phases of bipolar disorder. This study was designed to provide preliminary evidence for the safety and efficacy of a new anticonvulsant, lamotrigine, in adult patients with bipolar disorder who had been inadequately responsive to or intolerant of prior pharmacotherapy.

METHOD

A 48-week, open-label, prospective trial was conducted in 75 patients with bipolar I or bipolar II disorder. Lamotrigine was used as adjunctive therapy (N = 60) or monotherapy (N = 15) in patients presenting in depressed, hypomanic, manic, or mixed states.

RESULTS

Of the 40 depressed patients included in the efficacy analysis, 48% exhibited a marked response and 20% a moderate response as measured by reductions in 17-item Hamilton Depression Rating Scale scores. Of the 31 with a hypomanic, manic, or mixed state, 81% displayed a marked response and 3% a moderate response on the Mania Rating Scale. From baseline to endpoint, the depressed patients exhibited a 42% decrease in Hamilton depression scale scores, and the patients presenting with hypomania, mania, or a mixed state exhibited a 74% decrease in Mania Rating Scale scores. The most common drug-related adverse events were dizziness, tremor, somnolence, headache, nausea, and rash. Rash was the most common adverse event resulting in drug discontinuation (9% of patients); one patient developed a serious rash and required hospitalization.

CONCLUSIONS

These open-label data provide preliminary evidence that lamotrigine may be an effective treatment option for patients with refractory bipolar disorder; however, potential benefits must be weighed against potential side effects, including rash.

Lamotrigine--an effective mood stabilizer?

OBJECTIVE

To review the literature regarding the use of lamotrigine as a mood stabilizer, and to discuss its efficacy in treating this condition.

DATA SOURCES

Data were obtained from MEDLINE, Micromedex, and Cochrane collaboration searches from January 1985 to July 1998.

DATA SUMMARY

There are insufficient data to confirm that lamotrigine is an effective mood stabilizer. There are no controlled studies, and the current evidence is from case studies and open trials. Furthermore, only one study shows any evidence of effectiveness in the manic phase, although this may be because the data tend to relate to a treatment-refractory population.

CONCLUSIONS

From the current evidence, lamotrigine cannot be recommended as a mood stabilizer except when conventional therapies have failed.

Anticonvulsant Use in the Treatment of Bipolar Disorder: A Primer for Primary Care Physicians

Primary care physicians may be directly or indirectly involved in the management of the bipolar patient. Bipolar affective illness is a chronic, recurrent disorder. Patients, their families and support systems, and the general public can face profound and enduring consequences if the illness is untreated or poorly treated. Consequently, increasing attention has been directed at developing treatment strategies to control symptoms associated with bipolar disorder. While lithium has been the mainstay of treatment for many years, recent investigations have demonstrated the utility of a number of anticonvulsant medications in bipolar disorder. This review will discuss the literature on anticonvulsant efficacy in bipolar disorder in light of the treatment guidelines set forth by the Bipolar Treatment Expert Consensus Panel and the American Psychiatric Association. To orient the clinician, issues related to anticonvulsant use, dosing, adverse effects, and drug interactions are also discussed.

Omega-3 fatty acids and bipolar disorder: a review

The important role of the omega-3 fatty acids in the pathophysiology and treatment of bipolar disorder is now supported by a substantial body of indirect and direct evidence. This paper will describe the clinical and pharmacological features of bipolar disorder, review the available data regarding omega-3 fatty acids in bipolar disorder and provide recommendations for future research.

Mood stabilizers in children and adolescents

OBJECTIVE

The efficacy of mood stabilizers in children and adolescents has not been studied adequately. This article will review existing studies and highlight some important issues in designing future studies on these agents.

METHOD

Electronic databases including Medline, Psycholnfo, and CRISP were searched for data in children receiving compounds that have mood-stabilizing properties in adults.

RESULTS

Some open clinical data and an extremely modest amount of controlled research data suggest lithium, carbamazepine, and valproate may be effective mood stabilizers in children and adolescents. There are no controlled data on other potential mood stabilizers in children.

CONCLUSIONS

The disorders that may be responsive to mood stabilizers are among the most morbid in child psychiatry. More studies are needed to clarify the efficacy of these compounds in children and adolescents and to provide a rational basis for choosing among them.

The efficacy of lamotrigine in rapid cycling and non-rapid cycling patients with bipolar disorder

BACKGROUND

Patients with bipolar disorder (BD) who have rapid cycling features are often treatment refractory. Clear and conclusive evidence regarding effective treatments for this group is not available.

METHODS

Patients with diagnoses of refractory bipolar disorder who were currently experiencing manic, mixed, depressive, or hypomanic episodes were treated with lamotrigine as add-on therapy (60 patients) or monotherapy (15 patients). We compared the efficacy of lamotrigine in the 41 rapid cycling and 34 non-rapid cycling patients with BD.

RESULTS

Improvement from baseline to last visit was significant among both rapid cycling and non-rapid cycling patients for both depressive and manic symptomatology. For patients entering the study in a depressive episode, improvement in depressive symptomatology was equivalent in the two groups. Among patients entering the study in a manic, mixed, or hypomanic episode, those with rapid cycling improved less in manic symptomatology than did non-rapid cycling patients. Among rapid cycling patients with initial mild-to-moderate manic symptom severity, improvement was comparable to that in non-rapid cycling subjects; however, the subset of rapid cycling patients with severe initial manic symptomatology had little improvement in mania. Rapid cycling patients had earlier onset and more lifetime episodes of mania, depression, and mixed mania.

CONCLUSIONS

Lamotrigine was generally effective and well tolerated in this group of previously non-responsive, rapid cycling bipolar patients.

Lamotrigine for the treatment of bipolar disorder: a clinical case series

BACKGROUND

Recently, a number of new agents have become available to treat bipolar disorder, however many patients may not respond fully even when used in combination. Early reports in epilepsy studies suggested mood-related effects of lamotrigine treatment, as have preliminary reports in bipolar patients.

METHODS

Seventeen patients meeting DSM-IV criteria for bipolar I (n = 9) or bipolar II (n = 8) disorder displaying affective symptoms and a past history of inadequate response or tolerability to at least two standard mood stabilizing agents were recruited through the Stanley Foundation Bipolar Network and treated with the new anticonvulsant lamotrigine in an add-on, open-label study. Response to therapy was assessed using the Clinical Global Impression Scale modified for bipolar disorder.

RESULTS

The mean dose of lamotrigine was 187+/-157 mg/day (range 50-600 mg/day) for a mean duration of 159+/-109 days (range 14-455 days). Eleven (65%) patients were rated as very much or much improved. Lamotrigine was well tolerated, and may have mood stabilizing and antidepressant properties in some patients with bipolar disorder.

LIMITATIONS

The study is hypothesis generating because it was uncontrolled and open. Controlled studies are warranted.

CONCLUSIONS

This preliminary report supports clinical improvement for both mood cycling and depression in patients with bipolar disorder treated with lamotrigine.

Mood stabilizers and anticonvulsants

This article provides pediatricians and other clinicians who treat children and adolescents with a working knowledge of mood stabilizers and their potential uses in children and adolescents with mood and behavior disorders. Mood stabilizers are ubiquitous agents that are often effective in the treatment of children and adolescents with bipolar disorders or conduct disorders and mentally retarded patients with aggressive behavior. The authors' also discuss mechanisms of action, pharmacokinetics, dosing, drug interactions, and potential uses. Following these medication details, specific information concerning the diagnosis and treatment of several child and adolescent mood and behavior disorders, and in which treatment with mood stabilizers may be helpful, is presented.

Lamotrigine inhibits monoamine uptake in vitro and modulates 5-hydroxytryptamine uptake in rats

Lamotrigine is a novel anticonvulsant drug which also stabilises mood in bipolar illness via an unknown mechanism. We report the concentration-dependent inhibition of 5-hydroxytryptamine (5-HT) uptake in both human platelets and rat brain synaptosomes (IC50s were 240 and 474 microM, respectively) by lamotrigine. Synaptosomal uptake of noradrenaline (IC50 239 microM) and dopamine (IC50 322 microM) was also inhibited. Tetrodotoxin failed to modulate 5-HT uptake suggesting that sodium channel blockade does not mediate the lamotrigine effect. Lithium, sodium valproate, zonisamide, and carbamazepine all possess anti-manic activity but only the latter inhibited 5-HT uptake. The inhibition of the p-chloroamphetamine-induced 5-HT syndrome in rats suggests that lamotrigine also inhibits 5-HT uptake in vivo. These effects probably reflect an affinity for biogenic amine transporters. However, at present, it remains uncertain whether, at clinically effective doses, these effects contribute significantly to the efficacy of lamotrigine in bipolar illness.

Use of topiramate, a new anti-epileptic as a mood stabilizer

RATIONALE

Because some anti-epileptic drugs (AEDs) are effective in bipolar affective disorders, the new AED topiramate (TPM) may be effective in psychiatric illnesses. TPM was evaluated in mood disorders refractory to previous therapies including newer AEDs.

METHODS

Charts of 58 consecutive patients, 39 outpatients (15 males, 24 females) and 19 inpatients (6 males, 13 females) were reviewed. TPM 25 mg. b.i.d. was added to existing therapy and titrated in 50 mg increments every 3-7 days. Improvement was rated on a Likert global assessment scale of marked, moderate, mild, or no improvement or worse, based on quality of sleep, appetite, mood, and concentration.

RESULTS

Of the 58 patients with psychiatric disorders, 44 patients had rapid cycling bipolar disorders characterized by manic, hypomanic, or mixed episodes. Eighteen patients had previously failed to respond to lamotrigine and/or gabapentin in addition to conventional mood stabilizers. Fourteen were Bipolar I, six Bipolar II, and seven mixed, ten patients had cyclothymic disorder, seven had bipolar disorder not otherwise specified. Of the remaining 14 patients, nine had schizoaffective disorder, three patients had dementia and two had psychosis. Mean duration of TPM treatment was 16.0 weeks; mean TPM dosage approximately 200 mg/day. Thirty-six of 58 (62%) patients exhibited marked or moderate improvement, usually within days or weeks. Twenty-three of 44 (52%) patients with bipolar affective disorders showed marked or moderate improvement. Minimal/no improvement was observed in 16; six were rated as worse. Adverse events included delirium in one patient with Bipolar Disorder Type I who overmedicated with TPM (800 mg) and tranylcypromine sulfate (170 mg) combined with alcohol. Other adverse effects were minor and included: paresthesias, somnolence, fatigue, impaired concentration and memory, nausea, and diarrhoea.

LIMITATIONS

This study was performed in a nonrandom open and retrospective fashion. Therefore, any findings are limited by the design of this study.

CONCLUSION

TPM may be useful in patients with mood disorders unresponsive to traditional therapy and warrants further clinical investigation.

An open study of lamotrigine in refractory bipolar depression

Bipolar depressed patients (n = 22) who were refractory to treatment with a combination of divalproex sodium (DVP) and another mood stabilizer or DVP and an antidepressant for 6 weeks were treated in an open naturalistic study with an addition of lamotrigine to DVP. Sixteen out of 22 (72%) responded by the end of week 4 and none developed rash or switched to mania. The results of this preliminary study suggest that lamotrigine may be useful in bipolar depression.