Fulminant hepatic failure induced by lamotrigine

Acute liver failure associated with lamotrigine in children with epilepsy: A report of two cases and thoughts on pharmacogenomics

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We describe two cases of pediatric acute liver failure after LTG administration in children with epilepsy.

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Higher dose, rapid titration, and in combination with valproic acid have been linked with higher incidence of LTG hepatotoxicity.

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It is difficult to identify any single nucleotide polymorphism associated with LTG that causes liver injury or to guide clinical decision making at present.

Pediatric acute liver failure (PALF) is a rare and life-threatening clinical syndrome for which drug-induced liver injury is a cause. Lamotrigine (LTG) is generally a safe and effective antiseizure medication, and PALF related to LTG has rarely been reported. Here, we describe two cases of PALF associated with LTG in children with epilepsy. In both patients, LTG was used in combination with valproic acid at an initial dose exceeding the recommended dose, which increased the risk of adverse reactions. In addition, single nucleotide polymorphisms of genes associated with the pharmacokinetics and pharmacodynamics of LTG were selected for pharmacogenomic testing. However, the results revealed that genotypes of the patients had variable effects on the serum concentration and therapeutic responsiveness of LTG and therefore did not explain the clinical manifestations well. The findings of this case report caution clinicians to be aware of the risk of liver failure when using antiseizure medication in polytherapy, especially LTG in combination with valproic acid. When administered to children, the recommended dosage of LTG should be strictly followed. Further pharmacogenomic studies are needed to help improve the efficacy and safety of epilepsy treatment in the future.

Drug-induced liver injury with skin reactions: Drugs and host risk factors, clinical phenotypes and prognosis

While dermatologic manifestations of adverse drug reactions are frequent, drug-induced liver injury is rare. Numerous drugs are implicated in either Drug-Induced Liver Injury or Drug-Induced Skin Injury. However, concomitant Drug-Induced Liver Injury and Drug-Induced Skin Injury are uncommon, not well characterized and appear to be caused by a limited number of drugs. These are often associated with immuno-allergic or hypersensitivity features such as fever, skin rash, blisters or peeling of skin, eosinophilia, lymphadenopathy and mucositis. Liver injury can range from asymptomatic elevation of liver biochemical tests to severe hepatitis and acute liver failure needing liver transplantation. Severe cutaneous adverse reaction, particularly drug reaction with eosinophilia and systemic symptoms is commonly associated with internal organ involvement, the liver being the most frequently involved in approximately 90% of the cases. In Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis, abnormalities in liver biochemistry tests are common but severe liver disease is rare. There is a strong association of Human Leukocyte Antigen genotype with both drug reaction with eosinophilia and systemic symptoms and Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis. It is likely that the delayed immune-mediated reaction triggering skin reaction is also responsible for hepatitis. Drug-specific lymphocytes are found in the organs involved and also in circulating blood, which along with the cytokines and chemokines play a role in pathogenesis. Anti-epileptic drugs, allopurinol, sulfonamides, antibiotics and nevirapine are the top five causes of concomitant liver and skin injury. This review will focus on drug and host factors causing concomitant Drug-Induced Skin Injury and Drug-Induced Liver Injury and discuss the characteristics of liver involvement in patients with severe cutaneous adverse reaction.

Liver Illness and Psychiatric Patients

Patients with psychiatric disorders are usually more exposed to multiple somatic illnesses, including liver diseases. Specific links are established between psychiatric disorders and alcohol hepatitis, hepatitis B, and hepatitis C in the population as a whole, and specifically in drug abusers. Metabolic syndrome criteria, and associated steatosis or non-alcoholic steato-hepatitis (NASH) are frequent in patients with chronic psychiatric disorders under psychotropic drugs, and should be screened. Some psychiatric medications, such as neuroleptics, mood stabilizers, and a few antidepressants, are often associated with drug-induced liver injury (DILI). In patients with advanced chronic liver diseases, the prescription of some specific psychiatric treatments should be avoided. Psychiatric disorders can be a limiting factor in the decision-making and following up for liver transplantation.

Liver dysfunction induced by systemic hypersensitivity reaction to lamotrigine: case report

Lamotrigine is an anticonvulsant drug used to treat partial and generalized seizure disorders. Hypersensitivity to lamotrigine usually causes mild symptoms such as fever, rash, and slight invasion of internal organs. However, a 33-year-old male patient who was admitted with Stevens-Johnson syndrome after taking lamotrigine for 15 days experienced hepatic failure and died 5 days after admission. This case demonstrates the importance of realizing that lamotrigine can lead to fatal hepatic failure, and that tests for the normal liver function should be performed when administering lamotrigine.

Single centre 20 year survey of antiepileptic drug-induced hypersensitivity reactions

BACKGROUND

Epilepsy is a chronic neurological disease which affects about 1% of the human population. There are 50 million patients in the world suffering from this disease and 2 million new cases per year are observed. The necessary treatment with antiepileptic drugs (AEDs) increases the risk of adverse reactions. In case of 15% of people receiving AEDs, cutaneous reactions, like maculopapular or erythematous pruritic rash, may appear within four weeks of initiating therapy with AEDs.

METHODS

This study involved 300 epileptic patients in the period between September 1989 and September 2009. A cutaneous adverse reaction was defined as a diffuse rash, which had no other obvious reason than a drug effect, and resulted in contacting a physician.

RESULTS

Among 300 epileptic patients of Neurological Practice in Kielce (132 males and 168 females), a skin reaction to at least one AED was found in 30 patients. As much as 95% of the reactions occurred during therapies with carbamazepine, phenytoin, lamotrigine or oxcarbazepine. One of the patients developed Stevens-Johnson syndrome.

CONCLUSION

Some hypersensitivity problems of epileptic patients were obviously related to antiepileptic treatment. Among AEDs, gabapentin, topiramate, levetiracetam, vigabatrin, and phenobarbital were not associated with skin lesions, although the number of patients in the case of the latter was small.

Lamotrigine and its applications in the treatment of epilepsy and other neurological and psychiatric disorders

Lamotrigine is a broad-spectrum antiepileptic drug, initially approved in 1994 for the adjunctive treatment of partial seizures in adults and for the generalized seizures of Lennox-Gastaut syndrome in pediatric (>2 years old) and adult populations. Its role in the treatment of bipolar disorder type I has also been well established. In addition, lamotrigine has been successfully used for the management of other neurological conditions such as migraines and neuropathic pain, and preliminary data show promising results. It has favorable pharmacokinetic properties and is generally well tolerated. The small risk of serious skin rash can be minimized with slow titration of the drug and dose adjustment with concomitant medications. Lamotrigine has demonstrated particular benefit in the treatment of women and elderly patients with epilepsy.

Lamotrigine induced DRESS syndrome

Drug rash with eosinophilia and systemic symptoms (DRESS) syndrome is a rare and life-threatening delayed drug hypersensitivity reaction characterized by skin eruption, fever, lymphadenopathies, and visceral involvement. Here, we are presenting a 12 year old boy, who developed rare but life threatening DRESS syndrome due to Lamotrigine. Early detection and treatment led to his rapid recovery. This case is presented to highlight the importance of early detection of rare fatal syndrome.

The safety and tolerability of newer antiepileptic drugs in children and adolescents

The newer antiepileptic drugs (AEDs) provide more therapeutic options and overall improved safety and tolerability for patients. To provide the best care, physicians must be familiar with the latest tolerability and safety data. This is particularly true in children, given there are relatively fewer studies examining the effects of AEDs in children compared with adults. Since we now have significant paediatric literature on each of these agents, we provide a comprehensive and current literature review of the newer AEDs, focusing on safety and tolerability data in children and adolescents. Because the safety profiles in children differ from those in adults, familiarity with this literature is important for child neurologists and other paediatric caregivers. We have organized the data by organ system for each AED for easier reference.

Life-threatening organ failure after lamotrigine therapy

We describe an 11-year-old girl with a seizure disorder who developed fever, rash, rhabdomyolysis, and multiorgan failure 2 weeks after commencing a transition from sodium valproate to lamotrigine therapy. To our knowledge, this patient represents the most severe life-threatening hypersensitivity lamotrigine reaction described in the pediatric literature. We recommend caution when prescribing lamotrigine to children on concomitant sodium valproate, and immediate discontinuation of lamotrigine and the provision of aggressive supportive care in patients with features of lamotrigine hypersensitivity.

Lamotrigine-associated reversible severe hepatitis: a case report

INTRODUCTION

Anticonvulsant hypersensitivity syndrome is a severe idiosyncratic reaction to antiepileptic drugs. We report a case of a woman with lamotrigine-associated hepatitis who recovered spontaneously with supportive treatment.

CASE REPORT

A 43-year-old woman was being treated with oxcarbazepine for depression and was started on lamotrigine 2 weeks prior to her presentation. The patient then developed nausea and a generalized pruritic macular rash, and was found to have elevated liver enzymes, which peaked at AST, 6079 IU/L; ALT, 6900 IU/L; total bilirubin, 3.9 mg/dL(66.7 micromol/L); alkaline phosphatase, 149 IU/L; international normalized ration (INR), 1.9. The patient showed no signs of encephalopathy and her clinical examination was essentially normal except for very mild jaundice and a diffuse erythematous pruritic macular rash. The patient was hydrated and managed with supportive care. On the third day of hospitalization, her liver enzymes had improved substantially and she was discharged. At follow-up 1 month later the patient's liver enzymes were within the normal range.

DISCUSSION

We hypothesize that lamotrigine was directly responsible for the patient's rash and liver impairment given the time sequence of drug introduction and resolution of symptoms and liver enzyme abnormality once the drug was withdrawn. The patient suffered severe transaminitis when lamotrigine was added to oxcarbazepine, which resolved after termination of the medication and supportive management. We recommend monitoring the hepatic function in patients who have just been initiated on lamotrigine, especially if they develop jaundice.

Hepatotoxicity associated with antiepileptic drugs

BACKGROUND

Drug-induced liver injury associated with antiepileptic drugs (AED) is well recognized. The frequency of the most common AED is rare but the consequences can be very serious leading to death or liver transplantation due to acute liver failure induced by these drugs.

CLINICAL FEATURES

Hypersensitivity features are found in more than 70% of patients with phenytoin-induced liver injury, whereas this is only observed in 30% of carbamazepine-associated hepatotoxicity and very rarely with valproate (VPA)-induced liver injury.

PATHOPHYSIOLOGY

The underlying mechanisms behind hepatotoxicity induced by AED are not clear. Reactive metabolites from AED can, in some cases, lead to direct cytotoxicity and liver cell necrosis, whereas in other cases this may lead to neoantigen formation inducing immunoallergic mechanisms.

TREATMENT

No specific therapy is of proved value in severe hepatotoxicity due to AED. However, N-acetylcystein is an appropriate treatment in patients with clinically significant liver injury due to phenytoin and carbamazepine. In patients with VPA-associated liver injury, carnitine that is an important co-factor in the mitochondrial beta-oxidation of fatty acids is the recommended treatment. Early referral of patients with severe liver reactions and coagulopathy to liver transplant centers before encephalopathy can be the difference between liver transplantation and death.

Rash and Liver Dysfunction Related to Lamotrigine Therapy

Objective:

To report a case of rash and liver dysfunction associated with lamotrigine treatment.

Case Summary:

An 81-year-old woman with a history of bipolar disorder presented to the emergency department with complaints of fever, chills, nausea, and headache. Two weeks prior to presentation, liver enzymes were normal. Lamotrigine 50 mg/day and sustained-release bupropion 200 mg/day were started after discontinuation of citalopram. The patient had previous exposure to bupropion and documented rash with exposure to penicillin and sulfa. On admission, laboratory tests revealed slightly elevated liver enzymes and slightly low serum albumin. All medications were continued. On hospital day 3, a diffuse maculopapular rash developed on the patient's chest, abdomen, neck, and upper extremities, which was pruritic and warm to the touch. Both lamotrigine and bupropion were discontinued. Liver enzymes increased to more than 3 times the upper limit of normal, and serum albumin decreased. Liver function tests improved on day 6, and the rash resolved.

Discussion:

Predictive risk factors associated with lamotrigine-induced rash and liver dysfunction include rapid dose titration, previously reported rash with other medications, age, and concurrent interacting medications. More serious adverse effects, such as Stevens–Johnson syndrome and fulminant hepatic failure, have also been associated with lamotrigine treatment. If rash appears at any time during treatment, lamotrigine must be discontinued. According to the Naranjo probability scale, an association between lamotrigine and rash and liver dysfunction could be considered probable in this case.

Conclusions:

A faster than recommended dose titration may lead to lamotrigine-induced adverse effects such as rash and liver dysfunction in patients with risk factors.

Antiepileptic drugs and liver disease

Antiepileptic drugs (AEDs) are no longer restricted to the treatment of epilepsy. These are widely used in a broad spectrum of psychiatric and neurological disorders. Liver plays a major role in the metabolism of a majority of these drugs. Hepatotoxicity is rare, but a real concern when initiating therapy. Likewise, liver disease can adversely affect the biotransformation of some of these drugs. This manuscript addresses the significance of elevated liver enzymes associated with AED use, the role of therapeutic drug monitoring, pharmacokinetics during liver disease and potential risk of hepatotoxicity.

Prospective surveillance of acute serious liver disease unrelated to infectious, obstructive, or metabolic diseases: epidemiological and clinical features, and exposure to drugs

BACKGROUND/AIMS

Acute serious liver disease which is unrelated to infectious, obstructive, or metabolic disease is uncommon. Many drugs have been implicated. Data on its epidemiology are scarce. We performed a population-based prospective study of acute serious liver disease in Catalonia (Spain).

METHODS

A collaborating hospital network was set up. All patients with acute serious liver disease and negative viral hepatitis serological markers, without an obvious cause of liver disease, were included.

RESULTS

The incidence of acute serious liver disease was 7.4 per 10(6) inhabitants per year (95% CI; 6.0-8.8), which increased with age. The incidence of hepatocellular acute serious liver disease (3.84 per 10(6) per year) was greater than that of cholestatic and mixed patterns. The case-fatality ratio was 11.9% and mortality 0.8 per million person-years. The risk of death was similar among patients with hepatocellular and cholestatic patterns. Non-steroidal antiinflammatory drugs, analgesics, and antibacterials were the most frequently used drugs.

CONCLUSIONS

Acute serious liver disease which is unrelated to infectious, obstructive, or metabolic disease is rare. Its incidence increases with age. The prognosis of cholestatic acute serious liver disease does not significantly differ from that of the hepatocellular pattern. Non-steroidal antiinflammatory drugs, analgesics, and antibacterials were the most common drugs likely to be responsible for acute liver disease.

Fatal progressive hepatic necrosis associated with lamotrigine treatment: a case report and literature review

We present a case of fatal, progressive hepatotoxicity in a patient treated with lamotrigine. After presenting with a rash and fever, she developed elevated liver function tests and clinical sequelae of hepatic failure. The subacute course of her progressive liver damage is documented in serial liver biopsies. While her initial biopsy showed approximately 50% hepatocyte necrosis, her post mortem examination performed three weeks later displayed massive hepatic necrosis with extensive bile duct proliferation. Although she was taking other antipsychotics at the time, her clinical course best parallels other reports of lamotrigine-associated hepatotoxicity. Here we discuss not only the clinicopathologic findings of this case but also review the pertinent literature.

Life-threatening adverse events of antiepileptic drugs

Treating a patient with antiepileptic drugs (AEDs) may give rise to unexpected life-threatening adverse events. Despite extensive experimental and clinical testing to ensure safety, most AEDs on the market have been associated with cases of severe cutaneous reactions, serious hematological disorders, or hepatic failure. Most of these disorders emerge as idiosyncratic immune-mediated disease or are related to toxic metabolic products of the AEDs. Early diagnosis is the only means of reducing the harmful, potentially fatal effects of these reactions. A high degree of suspicion, knowledge of risk factors, and close physician-patient contact increases the likelihood of early diagnosis and treatment. When diagnosed, severe reactions must be fully documented and reported to health authorities. The very rare occurrence of life threatening events should not, in general, limit treatment decision-making. Future epidemiological, chemical, and genetic research might provide methods for ascertaining which patients are at risk, so undue exposure can be avoided.

Lamotrigine

Lamotrigine is a newly available antiepileptic drug with a broad spectrum of efficacy and a tolerability profile that is favorable for use in many patients. Problems with rash are related to rate of dose ascension and drug interactions with valproate. Efficacy in treatment of mood disorder and some pain syndromes will broaden the use of this unique compound.

Drug-induced liver disease

This year's review is divided into several sections: the first describes drug withdrawals and new general reviews of drug-induced liver disease (DILD), including a review of a classification of drug injury. We review agents newly described as causing DILD, and new reports of DILD from established agents appearing in the year 2000. New aspects regarding the treatment of acetaminophen toxicity are included, and in the final section we deal with prevention of DILD as well as issues surrounding the use of potentially hepatotoxic medications in patients with underlying chronic disease.

Therapeutic safety monitoring: what to look for and when to look for it

This review focuses on the safety problems associated with antiepileptic drugs (AEDs) as revealed by laboratory testing and clinical examination. There are two classes of side effects: (a) common and mild and (b) rare and severe. Allergic reactions to AEDs are common and usually mild. However, on rare occasions, they can progress to more severe cutaneous disorders, including Stevens-Johnson syndrome and toxic epidermal necrolysis. Severe allergic reactions to AEDs range from immune responses with fever to multiorgan dysfunction. Allergic rashes may be genetically or immunologically determined. Laboratory abnormalities produced by AEDs are common and mild, and include hepatic enzyme elevation associated with phenytoin and mild elevation in ammonia associated with valproate. Serious, although rare, idiosyncratic side effects, such as aplastic anemia, hepatotoxicity, and thrombocytopenia, have also occurred with AEDs. These reactions are largely confined to the "classic" AEDs. With the exception of felbamate, AEDs approved in the past decade have not been plagued by severe idiosyncratic reactions. Subtle endocrine abnormalities, including variations in thyroid function tests and bone metabolism, and the often subclinical effects on peripheral nerve conduction produced by phenytoin and carbamazepine, are also examined.

Adverse event monitoring in lamotrigine patients: a pharmacoepidemiologic study in the United Kingdom

PURPOSE

This postmarketing surveillance study of lamotrigine (LTG) was performed to provide complementary data to large-scale Prescription-Event Monitoring study with a retrospective case records survey in five tertiary referral epilepsy centres in the United Kingdom.

METHODS

Adverse events were recorded and compared with those of two other new antiepileptic drugs (AEDs), gabapentin (GBP) and vigabatrin (VGB). All deaths were followed up and standardised mortality ratios (SMRs) were calculated. Serious adverse events were assessed individually.

RESULTS

A total of 2,701 patients was identified as being exposed to LTG and/or the comparators. It was necessary to exclude 1,326 patients because LTG and/or comparators had been commenced outside the study centres. The adverse events with LTG reported by this study were similar to those reported in the literature. Skin rash was the major adverse event. Life-threatening hepatic failure, acute exacerbation of ulcerative colitis, disseminated intravascular coagulation, and renal failure were reported. No death could be directly attributed to the use of LTG. The SMR was slightly higher than that reported in the literature; this probably reflects severity of epilepsy in the study population.

CONCLUSIONS

The safety profile of LTG was similar to that in the large-scale Prescription-Event Monitoring study and generally acceptable. Life-threatening adverse reactions were rare.

Adverse reactions to new anticonvulsant drugs

A lack of systematic pharmacoepidemiological studies investigating adverse drug reactions (ADRs) to anticonvulsants makes it difficult to assess accurately the incidence of anticonvulsant-related ADRs. Most of the available information in this regard stems from clinical trial experience, case reports and postmarketing surveillance, sources that are not, by any means, structured to provide precise data on adverse event epidemiology. For various ethical, statistical and logistical reasons, the organisation of structured clinical trials that are likely to provide substantial data on ADRs is extremely difficult. This review concentrates on current literature concerning serious and life-threatening ADRs. As with the older anticonvulsants, the majority of ADRs to newer anticonvulsants are CNS-related, although there are several that are apparently unique to some of these new drugs. Gabapentin has been reported to cause aggravation of seizures, movement disorders and psychiatric disturbances. Felbamate should only be prescribed under close medical supervision because of aplastic anaemia and hepatotoxicity. Lamotrigine causes hypersensitivity reactions that range from simple morbilliform rashes to multi-organ failure. Psychiatric ADRs and deterioration of seizure control have also been reported with lamotrigine treatment. Oxcarbazepine has a safety profile similar to that of carbamazepine. Hyponatraemia associated with oxcarbazepine is also a problem; however, it is less likely to cause rash than carbamazepine. Nonconvulsive status epilepticus has been reported frequently with tiagabine, although there are insufficient data at present to identify risk factors for this ADR. Topiramate frequently causes cognitive ADRs and, in addition, also appears to cause word-finding difficulties, renal calculi and bodyweight loss. Vigabatrin has been reported to cause seizure aggravation, especially in myoclonic seizures. There have been rare reports of other neurological ADRs to vigabatrin, such as encephalopathy, aphasia and motor disturbances. Vigabatrin-induced visual field constriction is the latest and most worrying ADR. Many questions regarding the nature of this potentially serious ADR remain unanswered, as no prospective controlled study examining the phenomenon has been published. Rare cases of behavioural ADRs and IgA and IgG2 deficiency associated with the use of zonisamide have been reported. However, relatively few patients so far have been exposed to this drug, and therefore more postmarketing information is required. The relatively late establishment of aplastic anaemia and hepatic failure as potentially fatal ADRs of felbamate, and of visual field constriction with vigabatrin, should serve as ample reminders that ADRs can appear at any time.

Newer anticonvulsants: comparative review of drug interactions and adverse effects

The tolerability and drug interaction profiles of 6 new anticonvulsants: oxcarbazepine, vigabatrin, lamotrigine, gabapentin, tiagabine and topiramate, are reviewed. In general, these new anticonvulsants are well tolerated and drug interaction problems are minor with the exception of the risk of failure of oral contraceptives during treatment with oxcarbazepine or topiramate. In this review, the clinical implications of the tolerability of these drugs are discussed for different patient groups. The choice of which new anticonvulsant for which patient depends upon individual factors, in particular, seizure type, tolerability and practical administration factors. Treating elderly patients may be complicated by an increased sensitivity to adverse effects as these patients very often receive polytherapy for accompanying diseases. Drugs with very simple pharmacokinetic properties may be preferred in this group. Women of childbearing age face specific problems related to the epilepsy and to treatment with anticonvulsants. These include impaired fertility, failure of oral contraceptives and the risk of birth defects. Some new anticonvulsants may be suggested in preference to classical drugs to avoid these problems, but the human experience with newer anticonvulsants is still limited and, therefore, so is knowledge of the risk of congenital malformations in the offspring of mothers taking anticonvulsants. Psychiatric and behavioural changes frequently complicate treatment of patients with mental retardation. Some of the new anticonvulsants, in particular those affecting the gamma-aminobutyric acid (GABA) system such as vigabatrin, seem to exacerbate this problem and should be used with caution in these patients.

Lamotrigine. A review of its use in childhood epilepsy

Lamotrigine is an antiepileptic agent that blocks use-dependent voltage-sensitive sodium channels, thereby preventing excitatory neurotransmitter release. However, this mechanism does not explain the broad range of clinical efficacy of this agent. In noncomparative trials, adjunctive lamotrigine (< or = 15 mg/kg/day) improved seizure control in children and adolescents with various refractory seizure types, with about 29 to 90% of patients showing a > or = 50% reduction in seizure frequency after > or = 3 months' treatment. Lamotrigine was particularly effective in generalised seizures, especially absence seizures and those related to the Lennox-Gastaut syndrome. In one placebo-controlled study, 33% of children and young adults (aged 3 to 25 years) with refractory Lennox-Gastaut syndrome had a reduction in seizure frequency of > or = 50% after 16 weeks of adjunctive lamotrigine treatment, compared with 16% of placebo recipients (p = 0.01). Significant reductions in seizure frequency when compared with placebo were also observed in patients with refractory generalised and partial seizures. The use of lamotrigine has also been associated with beneficial effects on cognition and behaviour. Adverse events associated with lamotrigine are primarily neurological, gastrointestinal and dermatological and are typically mild or moderate and transient with the exception of a potentially serious rash. Maculopapular or erythematous skin rash occurred in approximately 12% of paediatric patients (aged < 16 years) treated with lamotrigine and was the most common reason for treatment discontinuation. More severe forms of rash, including Stevens-Johnson syndrome, occasionally occurred, with a 3-fold higher incidence in children (approximately 1%) than adults (approximately 0.3%). However, lamotrigine treatment in paediatric trials was generally given at higher initial doses and faster dose escalations than recently revised recommendations. These factors, as well as concomitant use of valproic acid (valproate sodium), are associated with an increased risk of rash.

CONCLUSION

Although published clinical evidence is still limited in paediatric populations, lamotrigine is an effective and generally well tolerated broad-spectrum agent for adjunctive treatment of refractory seizures in children, most notably in those with Lennox-Gastaut syndrome. Results of direct comparisons with other antiepileptic agents are needed to determine more clearly the place of lamotrigine, particularly relative to newer agents, in the treatment of childhood epilepsy. The potential for serious rash in recipients of lamotrigine should also be kept in mind. Nonetheless, lamotrigine is a welcome addition to the available treatments for refractory childhood epilepsy, particularly Lennox-Gastaut syndrome.

Successful re-introduction of lamotrigine after initial rash

The aim of this study was to determine whether lamotrigine can be re-introduced safely and with a benefit in young people who previously had a mild rash associated with the first introduction of this drug. In the first 150 young people (5-19 years old) treated with lamotrigine in a special centre for epilepsy, seven developed a mild rash soon after starting the drug. In none of these cases was the rash severe, nor was there any mucous membrane involvement. The lamotrigine was stopped immediately when the rash was identified and was subsequently re-introduced, using a special very-low-dose-escalation regime, starting with 0.1 mg /day total daily dose, after periods ranging from 47 to 236 days. It was possible to re-introduce the lamotrigine without recurrence of persistent rash and without any adverse effects in all seven cases. The re-introduction of lamotrigine was associated with improvement in five of the seven cases. It is recommended that lamotrigine is stopped as soon as any rash attributable to the drug develops but it may be possible to re-introduce the drug after mild rash using a very-slow-dose-escalation regime, with a benefit in at least some cases.

Potential hepatotoxicity of lamotrigine

Lamotrigine is a new antiepileptic drug that is effective for a broad range of seizures in adults and children. Three children with seizures of different causes who were treated with lamotrigine and developed reversible hepatotoxicity are reported. In one child, this therapy led to relatively severe hepatic failure that required and responded to aggressive therapy. Unlike most of the previously reported six patients with similar severe hepatic involvement, this patient's liver function and blood hepatic enzymes became normal. All three patients were on multiple drugs, and two were in epilepsia partialis continua secondary to encephalitis. Two of the patients had relatively rapid medication titration schedules. The close time relationship between the initiation of the lamotrigine therapy and the reversal of the liver abnormalities with lamotrigine discontinuation argues against a cause other than the lamotrigine; however, because of the complexity of the reported cases, the causality remains an assumption. Review of the literature revealed six other previously reported patients (five adults and one child) who had hepatotoxicity during lamotrigine therapy, with or without associated multisystem failure, and similar patient profiles. Lamotrigine is generally a safe and effective medication; however, it should be used with caution in patients on polytherapy and in those with complicated acute systemic and central nervous system conditions, such as fever, status epilepticus, epilepsia partialis, and encephalitis.

Anticonvulsant hypersensitivity syndrome: incidence, prevention and management

Although the anticonvulsant hypersensitivity syndrome was first described in 1950, confusion still abounds regarding the syndrome. The triad of fever, rash and internal organ involvement occurring 1 to 8 weeks after exposure to an anticonvulsant heralds this rare (1 in 1,000 to 10,000 exposures) but serious reaction. Aromatic anticonvulsants [phenytoin, phenobarbital (phenobarbitone) and carbamazepine] are the most frequently involved drugs; however, there have also been several cases of anticonvulsant hypersensitivity syndrome associated with lamotrigine. Fever, in conjunction with malaise and pharyngitis, is often the first sign. This is followed by a rash which can range from a simple exanthem to toxic epidermal necrolysis. Internal organ involvement usually involves the liver, although other organs such as the kidney, CNS or lungs may be involved. Hypothyroidism may be a complication in these patients approximately 2 months after occurrence of symptoms. The aromatic anticonvulsants are metabolised to hydroxylated aromatic compounds, such as arene oxides. If detoxification of this toxic metabolite is insufficient, the toxic metabolite may bind to cellular macromolecules causing cell necrosis or a secondary immunological response. Cross-reactivity among the aromatic anticonvulsants may be as high as 75%. In addition, there is a familial tendency to hypersensitivity to anticonvulsants. Discontinuation of the anticonvulsant is essential in patients who develop symptoms compatible with anticonvulsant hypersensitivity syndrome. A minimum battery of laboratory tests, such as liver transaminases, complete blood count and urinalysis and serum creatinine, should be performed. Corticosteroids are usually administered if symptoms are severe. Patients with anticonvulsant hypersensitivity syndrome should avoid all aromatic anticonvulsants; benzodiazepines, valproic acid (sodium valproate) or one of the newer anticonvulsants can be used for seizure control. However, valproic acid should be used very cautiously in the presence of hepatitis. There is no evidence that lamotrigine cross-reacts with aromatic anticonvulsants. In addition, family counselling is a vital component of patient management.

The long-term use of gabapentin, lamotrigine, and vigabatrin in patients with chronic epilepsy

PURPOSE

To compare the long-term retention of gabapentin (GBP), lamotrigine (LTG), and vigabatrin (VGB) by patients with chronic epilepsy and the reasons for treatment discontinuation. To assess the likelihood of seizure freedom, seizure-related injury/hospital admission and mortality after these drugs were commenced.

METHODS

This was a retrospective case-records survey in five tertiary referral epilepsy centres in the U.K. The retention times on treatment (from initiation to discontinuation) for the different antiepileptic drugs (AEDs) were compared by using Kaplan-Meier survival analysis and Cox regression. Incidences of seizure freedom and seizure-related injury/hospital admissions and standardised mortality ratios were calculated.

RESULTS

There were 1,375 patients with chronic epilepsy included; 361 were taking GBP, 1,050 LTG, and 713 VGB. The retention of GBP, LTG, or VGB was <40% at 6 years. Fewer than 4% of patients become seizure free while taking one of the drugs. There was no reduction in mortality or seizure-related injury/admission.

CONCLUSIONS

The impact of these new AEDs on chronic epilepsy can be described only as modest. This view may be revised, however, as more experience is gained with new drugs in previously untreated patients.

Hypersensitivity reaction in a child due to lamotrigine

Lamotrigine is an anticonvulsant with a broad spectrum of activity that has been approved in the United States for use in adults with either partial or generalized seizures. This drug is being widely prescribed by pediatricians and neurologists because it is effective in children with idiopathic, resistant, generalized seizures and does not impair cognition. As with other anticonvulsants, a hypersensitivity syndrome has been described. Anticonvulsant hypersensitivity syndrome consists of the hallmark features of fever, rash, and lymphadenopathy. We report the first case of hypersensitivity syndrome in a child due to lamotrigine in which we believe the coadministration of valproic acid increased the duration of the reaction. Our patient had a high spiking fever, generalized morbilliform eruption, facial edema, lymphadenopathy, eosinophilia, atypical lymphocytosis, and an elevation in his liver function tests. The syndrome resolved with the discontinuation of the medication. Anticonvulsant hypersensitivity syndrome may occur with the administration of lamotrigine. Variable presentations may be seen, as hypersensitivity syndromes may be multisystem in nature. The prompt recognition of the signs and symptoms of this condition allows an accurate diagnosis so that the drug may be discontinued and other anticonvulsant treatment options instituted.

Antiepileptic drug hypersensitivity syndrome

The antiepileptic drug hypersensitivity syndrome (AHS) is an adverse drug reaction associated with the aromatic antiepileptic drugs (AEDs) phenytoin (PHT), carbamazepine (CBZ), phenobarbital (PB), and primidone. The syndrome is defined by the triad of fever, skin rash, and internal organ involvement. It can also be caused by other drugs, such as sulfonamides, dapsone, minocycline, terbinafine, azathioprine, and allopurinol. Diagnosis of AHS may be difficult because of the variety of clinical and laboratory abnormalities and manifestations and because the syndrome may mimic infectious, neoplastic, or collagen vascular disorders. The incidence is approximately 1 in 3,000 exposures. AHS starts with fever, rash, and lymphadenopathy, within the first 2-8 weeks after initiation of therapy. Internal manifestations include, among others, agranulocytosis, hepatitis, nephritis, and myostitis. AHS is associated with a relative excess of reactive oxidative metabolites of the AED. Insufficient detoxification may lead to cell death or contribute to the formation of antigen that triggers an immune reaction. Crossreactivity among PHT, CBZ, and PB is as high as 70-80%.

New drugs for epilepsy

Seizure freedom with no side-effects is the aim of treatment, and new antiepileptic drugs have not lived up to expectations; only a few patients with chronic epilepsy have been rendered seizure-free. These treatments have side-effects but their safety profile may be better than older alternatives, although chronic effects have not yet been established. This article reviews newly marketed antiepileptic drugs. It concentrates on shortcomings of current antiepileptic treatment and on the way drugs are developed. A new approach to treatment is long overdue. The development of rational antiepileptic treatments should be strongly encouraged. More clinically relevant paradigms need to be developed and incorporated into clinical trial programmes as these are presently biased in their designs towards regulatory issues.

Acute hepatic failure in a child treated with lamotrigine

An 8-year-old boy with a known seizure disorder that was being treated with lamotrigine developed acute hepatic failure. The patient, who had been well previously, presented with jaundice, elevated liver enzymes, and a coagulopathy. After discontinuation of lamotrigine and aggressive resuscitation, the patient made an uneventful recovery. We believe that the hepatic failure in our patient was secondary to the use of lamotrigine. We recommend careful monitoring of liver function when lamotrigine is administered.

Lamotrigine. An update of its pharmacology and therapeutic use in epilepsy

Lamotrigine is an antiepileptic agent which blocks voltage-dependent sodium channels, thereby preventing excitatory neurotransmitter release. Clinical evidence indicates that lamotrigine is effective against partial and secondarily generalised tonic-clonic seizures, as well as idiopathic (primary) generalised epilepsy. As monotherapy, lamotrigine 100 to 300 mg/day has similar medium term (30 to 48 weeks) efficacy to carbamazepine 300 to 1400 mg/day and phenytoin 300 mg/day against partial onset seizures and idiopathic generalised tonic-clonic seizures in adults with newly diagnosed epilepsy, and appears to be better tolerated than the older agents. As adjunctive therapy, lamotrigine (50 to 500 mg/day) has shown efficacy in short term ( < or = 6-months) placebo-controlled studies in adults with refractory partial epilepsy, reducing total seizure frequency (by < or = 60%) and producing improvement ( > or = 50% reduction in seizure frequency) in < or = 67% of patients. Both simple and complex partial seizures and secondarily generalised tonic-clonic seizures are reduced by lamotrigine, with generalised seizures (particularly absence seizures, atonic seizures and Lennox-Gastaut syndrome) tending to be more responsive than partial seizures. This reduction in seizure frequency is sustained on long term ( < or = 3 years) therapy and is reportedly accompanied by an improvement in psychological well-being. In children with refractory multiple seizure types, lamotrigine ( < or = 15 mg/kg/day; 400 mg/day) has proved effective as add-on therapy, with approximately equal to 40% of patients showing > or = 50% reductions in seizure frequency and approximately equal to 10 % achieving abolition of seizures after 3 months' treatment. Generalised seizures, including atypical and typical absence seizures, atonic and tonic seizures and Lennox-Gastaut syndrome are most responsive. The most common adverse events associated with lamotrigine are primarily neurological, gastrointestinal and dermatological. Maculopapular or erythematous skin rash, occasionally severe, occurs in approximately equal to 10% of patients and is the most common cause of treatment withdrawal. The risk of rash can, however, be minimised through adoption of a low, slow dosage titration schedule on initiating therapy. As monotherapy, lamotrigine produces less drowsiness than carbamazepine or phenytoin, and less asthenia and ataxia than phenytoin. Clinical experience would therefore suggest that lamotrigine is a particularly effective and generally well tolerated broad-spectrum agent for adjunctive treatment of both partial epilepsy and idiopathic generalised epilepsy in adults and children. Initial indications point to the drug filling an increasingly important future role in the monotherapy of newly diagnosed epilepsy.