Drug-Induced Liver Injury-Pharmacological Spectrum Among Children

Drug-induced liver injury (DILI) is one of the main causes of acute liver failure in children. Its incidence is probably underestimated, as specific diagnostic tools are currently lacking. Over 1000 known drugs cause DILI, and the list is expanding. The aim of this review is to describe DILI pathogenesis and emphasize the drugs accountable for child DILI in order to aid its recognition. Intrinsic DILI is well described in terms of mechanism, incriminated drugs, and toxic dose. Conversely, idiosyncratic DILI (iDILI) is unpredictable, occurring as a result of a particular response to drug administration, and its occurrence cannot be foreseen in clinical studies. Half of pediatric iDILI cases are linked to antibiotics, mostly amoxicillin-clavulanate, in the immune-allergic group, while autoimmune DILI is the hallmark of minocycline and nitrofurantoin. Secondly, antiepileptics are responsible for 20% of pediatric iDILI cases, children being more prone to iDILI caused by these agents than adults. A similar tendency was observed in anti-tuberculosis drugs, higher incidences being reported in children below three years old. Current data show growing cases of iDILI related to antineoplastic agents, atomoxetine, and albendazole, so that it is advisable for clinicians to maintain a high index of suspicion regarding iDILI.

The role of adrenergic neurotransmitter reuptake inhibitors in the ADHD armamentarium

INTRODUCTION

Adrenergic neurotransmitter reuptake inhibitors are gaining attention in treatment for attention-deficit hyperactivity disorder (ADHD). Due to their effects on norepinephrine, dopamine, and serotonin neurotransmission, they benefit both ADHD and comorbid disorders and have some other advantages including longer duration of action and fewer adverse effects compared to stimulants. There is continued interest in these agents with novel mechanisms of action in treatment of ADHD.

AREAS COVERED

The authors conducted a PubMed literature search using the following key words: 'ADHD' AND 'adrenergic reuptake inhibitors' OR 'nonstimulants' OR 'atomoxetine' OR 'Viloxazine' OR 'Dasotraline' OR 'Centanafadine' OR 'PDC-1421' OR 'Reboxetine' OR 'Edivoxetine' OR 'Bupropion' OR 'Venlafaxine' OR 'Duloxetine.' They reviewed FDA fact sheets of available medications for safety/tolerability studies and reviewed published clinical studies of these medications for treatment of ADHD.

EXPERT OPINION

Adrenergic neurotransmitter reuptake inhibitors fit the diverse needs of children and adolescents with ADHD with 1) poor tolerability to stimulants (e.g. due to growth suppression, insomnia, rebound irritability, co-morbid depression, anxiety and tic disorders, substance abuse or diversion concerns), 2) cardiac risks, and/or 3) need for extended duration of action. Their differences in receptor affinities and modulating effects support the unique benefits of individual agents.

Pediatric attention deficit hyperactivity disorder (ADHD): 2022 updates on pharmacological management

INTRODUCTION

Pediatric attention-deficit disorder (ADHD) impacts a significant percentage of the population world-wide. Pharmacologic treatments have been shown to be safe and effective for managing symptoms. Various medication formulations exist, and new medication agents are continually approved each year.

AREAS COVERED

This article offers an overview of ADHD, an overview of both stimulant and non-stimulant medication options as well as an overview of stimulant misuse. It explores the medication mechanisms of action and side effect profiles, as well as offering an in-depth summary of the novel agents recently approved and soon-to-be approved for use in youth. PubMed and Medline were utilized. Search terms included children, adolescents, ADHD, and medication. FDA package inserts were reviewed for all medications.

EXPERT OPINION

New formulations of medications include an evening administered, extended, and delayed-release form of methylphenidate (DR/ER MPH), a methylphenidate pro-drug (serdexmethylphenidate) and an amphetamine patch. The availability of a new SNRI (selective norepinephrine reuptake inhibitor), viloxazine extended-release (VER), and the pending approval of a triple reuptake inhibitor (centanafadine) provides welcome additions to the prescriber's toolbox.

Eating Patterns and Dietary Interventions in ADHD: A Narrative Review

Attention Deficit Hyperactivity Disorder (ADHD) is one of the most common neurodevelopmental disorders in childhood, affecting ~7% of children and adolescents. Given its adverse health outcomes and high healthcare and societal costs, other treatment options beyond pharmacotherapy have been explored. Case-control studies have shown that dietary patterns may influence the risk of ADHD, and specific dietary interventions have been proposed as coadjuvant treatments in this disorder. These include nutritional supplements, gut microbiome-targeted interventions with biotics, and elimination diets. The purpose of this review is to examine which dietary patterns are most associated with ADHD and to summarize the existing evidence for the clinical use of dietary interventions. The literature showed that non-healthy dietary patterns were positively associated with ADHD, whereas healthy patterns were negatively associated. As for nutritional supplements, only vitamin D and vitamin D + magnesium appeared to improve ADHD symptoms when baseline levels of vitamin D were insufficient/deficient. Regarding biotics, evidence was only found for Lactobacillus rhamnosus GG and for multi-species probiotic supplementation. Elimination diets have scarce evidence and lead to nutritional deficiencies, so caution is advised. Overall, more robust scientific evidence is required for these dietary interventions to be implemented as part of ADHD therapy.

Viloxazine for the Treatment of Attention Deficit Hyperactivity Disorder

PURPOSE OF REVIEW

Attention deficit hyperactivity disorder (ADHD) is a widely diagnosed neurodevelopmental disorder giving rise to symptoms of hyperactivity, impulsivity, and inattentiveness that can impair daily functioning. Stimulants, such as methylphenidate and amphetamines, are the mainstay of treatment for ADHD. However, nonstimulant drugs such as viloxazine, atomoxetine, guanfacine, and clonidine are becoming more popular due to minimal adverse effects when compared to stimulants.

RECENT FINDINGS

Viloxazine is a selective norepinephrine reuptake inhibitor (NRI) originally used to treat depression in adults with activity in both the noradrenergic as well as serotonergic pathways. Studies have demonstrated its efficacy for its use in the treatment of ADHD. Unlike stimulants, viloxazine has a decreased chance of substance abuse, drug dependance, and withdrawal symptoms upon the cessation of therapy. Additionally, dopamine levels in the nucleus accumbens after treatment with viloxazine are elevated considerably less in comparison with traditional stimulant ADHD treatments. Viloxazine provides an alternative, nonstimulant approach to treating ADHD.

SUMMARY

Viloxazine is a recently approved, non-stimulant medication functions by inhibiting the uptake of norepinephrine which has been seen to be decreased in patients with ADHD. When patients do not respond to first-line stimulants, cannot tolerate the side effects, or have contraindications to stimulants, viloxazine may be a nonstimulant option offering patients an increasing arsenal of medications to treat ADHD.

Retrospective analysis of adverse events associated with non-stimulant ADHD medications reported to the united states food and drug administration

Attention deficit hyperactivity disorder (ADHD) is one of the most common neurobehavioral disorders in children and although stimulant medications remain first line to treat the disorder, some families prefer nonstimulants. The goal is to analyze the adverse events (AE) associated with nonstimulant medications using post-marketing drug surveillance data. We aim to increase awareness and aide patient education. A retrospective study of adverse drug events with atomoxetine, clonidine, and guanfacine was performed using the Federal Drug Administration Adverse Event Reporting System (FAERS) Database. Results show that the most commonly reported AEs, as defined by FAERS, were ineffectiveness (9.91-14.15%) fatigue (8.93%), and somnolence (8.8-10.16%). Of those taking atomoxetine, suicidal and self-injurious ideation was reported to a similar degree amongst all age groups. Suicidal ideation was listed within the top 20 most reported AEs for all three medications. It is more likely that some patients will experience milder side effects. We suggest providing these data to patients to help overcome the stigma of starting medication, especially if they prefer nonstimulants. Serious AEs are still reported to a small degree, thus monitoring and consistent patient education remains important. We also recommend educating a wider demographic of patients about recognizing potential development of suicidal thoughts.

The Mechanism, Clinical Efficacy, Safety, and Dosage Regimen of Atomoxetine for ADHD Therapy in Children: A Narrative Review

Atomoxetine, a selective norepinephrine (NE) reuptake inhibitor, was approved for attention deficit/hyperactivity disorder (ADHD) treatment in children, adolescents and adults. We searched the database PubMed/MEDLINE (2000 to October 1, 2021). Only publications in English were considered. Atomoxetine inhibits the presynaptic norepinephrine transporter (NET), preventing the reuptake of NE throughout the brain along with inhibiting the reuptake of dopamine in specific brain regions such as the prefrontal cortex (PFC). The novel mechanism of atomoxetine also includes several new brain imaging studies and animal model studies. It is mainly metabolized by the highly polymorphic drug metabolizing enzyme cytochrome P450 2D6 (CYP2D6). Atomoxetine is effective and generally well tolerated. ADHD is often accompanied by multiple comorbidities. A series of studies have been published suggesting that atomoxetine is effective in the treatment of ADHD symptoms for children with various types of comorbidity. In some cases, it is possible that atomoxetine may have a positive influence on the symptoms of comorbidities. Atomoxetine can be administered either as a single daily dose or split into two evenly divided doses, and has a negligible risk of abuse or misuse. The latest guideline updated that clinical dose selection of atomoxetine was recommended based on both CYP2D6 genotype and the peak concentration. To have a more comprehensive understanding of atomoxetine, this review sets the focus on the mechanism, clinical efficacy and dosage regimen in detail, and also touches on those studies regarding adverse reactions of atomoxetine.

Clinical Practice Guideline for the Diagnosis, Evaluation, and Treatment of Attention-Deficit/Hyperactivity Disorder in Children and Adolescents

Attention-deficit/hyperactivity disorder (ADHD) is 1 of the most common neurobehavioral disorders of childhood and can profoundly affect children's academic achievement, well-being, and social interactions. The American Academy of Pediatrics first published clinical recommendations for evaluation and diagnosis of pediatric ADHD in 2000; recommendations for treatment followed in 2001. The guidelines were revised in 2011 and published with an accompanying process of care algorithm (PoCA) providing discrete and manageable steps by which clinicians could fulfill the clinical guideline's recommendations. Since the release of the 2011 guideline, the Diagnostic and Statistical Manual of Mental Disorders has been revised to the fifth edition, and new ADHD-related research has been published. These publications do not support dramatic changes to the previous recommendations. Therefore, only incremental updates have been made in this guideline revision, including the addition of a key action statement related to diagnosis and treatment of comorbid conditions in children and adolescents with ADHD. The accompanying process of care algorithm has also been updated to assist in implementing the guideline recommendations. Throughout the process of revising the guideline and algorithm, numerous systemic barriers were identified that restrict and/or hamper pediatric clinicians' ability to adopt their recommendations. Therefore, the subcommittee created a companion article (available in the Supplemental Information) on systemic barriers to the care of children and adolescents with ADHD, which identifies the major systemic-level barriers and presents recommendations to address those barriers; in this article, we support the recommendations of the clinical practice guideline and accompanying process of care algorithm.

Treatment of autonomic dysfunction in Parkinson disease and other synucleinopathies

Dysfunction of the autonomic nervous system afflicts most patients with Parkinson disease and other synucleinopathies such as dementia with Lewy bodies, multiple system atrophy, and pure autonomic failure, reducing quality of life and increasing mortality. For example, gastrointestinal dysfunction can lead to impaired drug pharmacodynamics causing a worsening in motor symptoms, and neurogenic orthostatic hypotension can cause syncope, falls, and fractures. When recognized, autonomic problems can be treated, sometimes successfully. Discontinuation of potentially causative/aggravating drugs, patient education, and nonpharmacological approaches are useful and should be tried first. Pathophysiology-based pharmacological treatments that have shown efficacy in controlled trials of patients with synucleinopathies have been approved in many countries and are key to an effective management. Here, we review the treatment of autonomic dysfunction in patients with Parkinson disease and other synucleinopathies, summarize the nonpharmacological and current pharmacological therapeutic strategies including recently approved drugs, and provide practical advice and management algorithms for clinicians, with focus on neurogenic orthostatic hypotension, supine hypertension, dysphagia, sialorrhea, gastroparesis, constipation, neurogenic overactive bladder, underactive bladder, and sexual dysfunction. © 2018 International Parkinson and Movement Disorder Society.

Use of atomoxetine and suicidal ideation in children and adolescents: Results of an observational cohort study within general practice in England

AIM

To investigate the association between atomoxetine, a drug used in the treatment of Attention Deficit Hyperactivity Disorder (ADHD), and suicidal ideation, within a cohort of 2-18-year-old patients in England.

METHODS

The study was conducted using the observational cohort technique of Modified prescription event monitoring (M-PEM). Patients prescribed atomoxetine were identified from dispensed prescriptions issued by primary care physicians. A customised postal GP questionnaire was used to capture outcome data for suicidal ideation. A matched pair cohort analysis was performed within patients to compare the risk of suicidal ideation in the period after starting atomoxetine with the risk prior to starting atomoxetine; this was stratified by age and concomitant use of methylphenidate. Additional information on patient characteristics, and events of interest was also collected; individual cases of suicidal ideation were qualitatively assessed for drug relatedness.

RESULTS

Of the final cohort (n=4509); 85.5% male (n=3857), median age 11 years (IQR: 9,14). Primary prescribing indication for atomoxetine was ADHD (n=4261, 94.6%). Almost a quarter of the cohort had been co-prescribed methylphenidate. Results of the matched pair cohort analysis indicated that the period after starting atomoxetine was not associated with an increase in the incidence of suicidal ideation compared to the period prior to starting treatment (RR: 0.71; CI: 0.48-1.07; P-value: 0.104). Individual case assessment of suicidal ideation suggested a causal association within a number of cases.

CONCLUSIONS

This study found no evidence of an increased risk of suicidal ideation during treatment with atomoxetine, compared to the period prior to starting treatment. Amongst age specific subgroups, this risk may change. Nonetheless, individual case assessment suggested a causal relationship in some patients, hence physicians need to be aware of the possibility of developing this event, and furthermore consider how best to detect it in this paediatric population. This study demonstrates the importance of combining quantitative statistical analyses with a qualitative case series assessment.

The Safety of Atomoxetine for the Treatment of Children and Adolescents with Attention-Deficit/Hyperactivity Disorder: A Comprehensive Review of Over a Decade of Research

Atomoxetine is a noradrenergic reuptake inhibitor prescribed for attention-deficit/hyperactivity disorder (ADHD) that first gained approval in the USA in 2002 and has been authorized in 97 countries worldwide. The aim of this paper is to comprehensively review publications that addressed one or more of seven major safety topics relevant to atomoxetine treatment of children and adolescents (aged ≥6 years) diagnosed with ADHD. While the review focuses on children and adolescents, publications in which data from patients aged >18 years and from 6 to 18 years were analyzed in the same dataset were included. Using a predefined search strategy, including agreement of two reviewers when selecting papers, reduced the potential for bias. Using this process, we identified 70 eligible papers (clinical trials, epidemiological studies, and case reports) across the seven topics. We also referred to the European Summary of Product Characteristics (SPC) and US label. We found 15 papers about suicidality, three about aggression/hostility, seven about psychosis/mania, six about seizures, seven about hepatic effects, 29 about cardiovascular effects, and 28 about growth and development. The main findings (i.e., those from the largest and most well-conducted studies/analyses) are as follows. A large register-based study of pediatric and adult patients (6818 received atomoxetine) calculated a hazard ratio of 0.96 for suicide-related events during treatment with atomoxetine, and a meta-analysis of 23 placebo-controlled studies (N = 3883), published in 2014, found no completed suicides and no statistically significant association between atomoxetine and suicidality. The frequency of aggression/hostility was not statistically significantly higher with atomoxetine, e.g., experienced by 1.6 % (N = 21/1308) of atomoxetine-treated patients versus 1.1 % (N = 9/806) of placebo-treated patients in one meta-analysis. Symptoms of psychosis and mania were mainly observed in patients with comorbid bipolar disorder/depression. Based on spontaneous reports, during a 2-year period when 2.233 million adult and pediatric patients were exposed to atomoxetine, the reporting rate for seizures was 8 per 100,000 patients. In the manufacturer's database, atomoxetine was a "probable cause" of three hepatic adverse events (AEs) (all reversible hepatitis), and 133 hepatic AEs had possible confounding factors and were "possibly related" to atomoxetine, during 4 years when atomoxetine exposure had reached about 4.3 million patients. Rare cases of severe liver injury are described in the US label and European SPC; a case requiring liver transplantation is described in the US label. In a comprehensive review of a clinical trials database (N = 8417 received atomoxetine), most pediatric patients experienced modest increases in heart rate and blood pressure, and 8-12 % experienced more pronounced changes (≥20 bpm, ≥15 to 20 mmHg). However, in three long-term analyses (≥2 years), blood pressure was within age norms, and few patients discontinued due to cardiovascular AEs. As described in the European SPC, QT interval prolongation is uncommon, e.g., in an open-label study, 1.4 % of 711 children and adolescents had prolonged QTc intervals (≥450 ms in males, ≥470 ms in females) that were not clinically significant at ≥3 years of treatment with atomoxetine. The European SPC warns about potential QT interval prolongation in patients with a personal or family history, or if atomoxetine is administered with other drugs that potentially affect the QT interval. Decreases in growth (weight and height gain) occurred and were greatest in patients of above average weight and height, but appeared to recover over 2-5 years of atomoxetine treatment. In conclusion, suicidality, aggression/hostility, psychosis, seizures, liver injuries, and prolonged QT interval are uncommon or rare in children and adolescents treated with atomoxetine, based on data from the predefined search and from the European SPC. Overall, the data that we assessed from our search do not suggest that associations exist between atomoxetine and suicidality or seizures. The data also suggest that an association may not exist between atomoxetine and aggression/hostility. While atomoxetine may affect the cardiovascular system, the data suggest these effects are not clinically significant in most patients. Reductions in growth appear to be reversible in the long term.

ADHD & Pharmacotherapy: Past, Present and Future: A Review of the Changing Landscape of Drug Therapy for Attention Deficit Hyperactivity Disorder

Attention deficit hyperactivity disorder (ADHD) is the most common neurobiological disorder in children, with a prevalence of ~6-7%^1,2 that has remained stable for decades². The social and economic burden associated with patients³, families, and broader systems (healthcare/educational) is substantial, with the annual economic impact of ADHD exceed $30 billion in the US alone⁴. Efficacy of pharmacotherapy in treating ADHD symptoms has generally been considerable with at least ¾ of individuals benefitting from pharmacotherapy, typically in the form of stimulants⁵. In this review, we begin by briefly reviewing the history of pharmacotherapy in relation to ADHD, before focusing (primarily) on the state-of-the-field on themes such as biophysiology, pharmacokinetics, and pharmacogenomics. We conclude with a summary of emerging clinical and research studies, particularly the potential role for precision therapy in matching ADHD patients and drug types.

A critical appraisal of atomoxetine in the management of ADHD

Attention-deficit/hyperactivity disorder (ADHD) is a common neurobehavioral disorder beginning in childhood and often continuing into adulthood. A wealth of data shows that ADHD symptoms respond well to pharmacological treatment. Stimulant medications, including amphetamine and methylphenidate, are most commonly used to treat ADHD. However, with the approval of atomoxetine (Strattera^®, [ATX]) by the US Food and Drug Administration in late 2002, an effective non-stimulant option became available. The US Food and Drug Administration approved ATX for the treatment of ADHD in children, adolescents, and adults. Although the effect size of ATX is generally lower than that of stimulants, the American Academy of Child and Adolescent Psychiatry Practice Parameter for the treatment of ADHD lists ATX as a first-line treatment option. ATX is widely prescribed and accounted for 6% of the prescriptions of ADHD visits in the US in 2010. Numerous trials have found that ATX improves quality of life and emotional lability in addition to core ADHD symptoms. Although some improvement may be seen in a patient as early as one week after the initiation of treatment, ATX generally takes longer to have a full effect. The median time to response using 25% improvement in ADHD symptoms in pooled trials was 3.7 weeks. Data from these trials indicate that the probability of symptom improvement may continue to increase up to 52 weeks after treatment is initiated. ATX has been shown to be safe and effective in combination with stimulants. It has also been studied systematically in subjects with ADHD and comorbid oppositional defiant disorder, anxiety, depression, and substance use disorders. The mechanism of action of ATX, its efficacy, and adverse events reported in trials is reviewed.

Atomoxetine treatment in adults with attention-deficit/hyperactivity disorder

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) is a CNS disorder that has its onset in childhood, but often persists into adulthood. There is growing recognition that adult ADHD can result in multiple negative consequences for individuals. ADHD is also often associated with a number of comorbid psychiatric disorders. Atomoxetine (ATX), a nonstimulant, selective noradrenergic reuptake inhibitor, was approved in the United States in 2002 for the treatment of ADHD in children and adolescents, as well as adults. We review here the safety and efficacy of ATX in adults with ADHD, including data in special populations, functional outcomes, as well as provider and patient real-world perceptions.

METHODS

We searched the databases Embase, MEDLINE and PsycINFO using the terms 'ADHD' and 'adult' and 'ATX' capturing publications from January 1, 1998, to March 27, 2014. Only publications in English were considered.

RESULTS

ATX demonstrated significantly greater improvement than placebo (PBO) on the Conners Adult ADHD Rating Scale-Investigator rated:Screening Version (CAARS-Inv:SV) in all trials (N = 6; total score difference ranged from -3.5 to -5.5). For long-term trials using the CAARS-Inv:SV, ATX demonstrated significantly greater improvement than PBO in three of four trials (total score differences ranged from -0.1 to -6.0). In short-term studies, ATX showed significantly greater improvement than PBO on the Adult ADHD Quality-of-Life scale total score in three of three studies, but results were mixed on the Sheehan Disability Scale. Three studies of ATX have reported statistically significant improvement (compared with PBO) on the Behavior Rating Inventory of Executive Function-Adult Version Self Report scale. The most common adverse events (occurring in ≥ 10% of patients taking ATX) were nausea, dry mouth, decreased appetite, insomnia and fatigue.

CONCLUSIONS

ATX is an important treatment option for the right patient. ATX can provide long-term, consistent symptom relief and functional improvement for adults with ADHD.

Liver enzyme levels in adolescent patients treated with buprenorphine and additional psychotropic agents

BACKGROUND

There are limited efficacy and safety data for buprenorphine/naloxone treatment in adolescents, and little is known about the incidence and prevalence of liver function abnormalities in young patients using buprenorphine/naloxone.

OBJECTIVES

To assess the changes in liver enzyme levels associated with buprenorphine/naloxone treatment and co-medication with psychotropic agents among opioid dependent subjects aged 15-18 years.

METHODS

Liver enzyme levels (ALT and AST) were evaluated among 59 adolescent subjects before and following eight weeks of buprenorphine/naloxone treatment.

RESULTS

The frequency of additional psychotropic use was 60%. The patients' mean liver enzyme levels at weeks 2 and 4 were significantly higher than the baseline (ALT: p < 0.0001 and p = 0.003, and AST: p < 0.0001 and p = 0.016, respectively). However, there was no statistically significant difference in AST and ALT levels between the baseline and week 8. The majority of the abnormalities seen were clinically nonsignificant elevations (less than two times the upper limit of normal). It is plausible that the abnormalities in liver enzymes could have been mediated by the use of psychotropic medications.

CONCLUSIONS

Buprenorphine/naloxone was well tolerated in most adolescent patients, besides clinically nonsignificant liver enzyme elevations. Psychotropic medications may have been associated with the liver enzyme changes early in the course of treatment. Nevertheless, given the relatively small number of adolescents studied to date with buprenorphine/naloxone, additional studies evaluating liver enzymes in young patients receiving buprenorphine/naloxone (and no other psychotropics) are needed.

Canadian guidelines on pharmacotherapy for disruptive and aggressive behaviour in children and adolescents with attention-deficit hyperactivity disorder, oppositional defiant disorder, or conduct disorder

OBJECTIVE

To develop evidence-based guidelines on pharmacotherapy for severe disruptive and aggressive behaviour in children and adolescents with attention-deficit hyperactivity disorder (ADHD), oppositional defiant disorder (ODD), or conduct disorder (CD). The guidelines assume that psychosocial interventions have been pursued but did not achieve sufficient improvement.

METHOD

A multidisciplinary consensus group used the Grading of Recommendations Assessment, Development and Evaluation approach for rating evidence quality and for grading recommendations. We conducted a systematic review of medications studied in placebo-controlled trials for treating disruptive and aggressive behaviour in children and adolescents with ADHD, ODD, or CD. We followed consensus procedures to make 1 of 4 recommendations for each medication: strong, in favour (↑↑); conditional, in favour (↑?); conditional, against (↓?); and strong, against (↓↓).

RESULTS

For children and adolescents with disruptive or aggressive behaviour associated with ADHD, psychostimulants received a strong recommendation in favour of use, while atomoxetine and alpha-2 agonists received a conditional recommendation in favour of use. If these patients do poorly with ADHD medications, the medication with the most evidence is risperidone. Risperidone also has the most evidence for treating disruptive or aggressive behaviour in the absence of ADHD. However, given risperidone's major adverse effects, it received only a conditional recommendation in favour of use. We recommended against using quetiapine, haloperidol, lithium, or carbamazepine because of the poor quality of evidence and their major adverse effects.

CONCLUSION

When severe disruptive or aggressive behaviour occurs with ADHD, medications for ADHD should be used first. Other medications have major adverse effects and, with the exception of risperidone, very limited evidence to support their use.

Attention-Deficit/Hyperactivity Disorder

Attention-deficit/hyperactivity disorder (ADHD) is a neurobiological condition of childhood onset with the hallmarks of inattention, impulsivity, and hyperactivity. Inattention includes excessive daydreaming, disorganization, and being easily distracted. Impulsivity manifests as taking an action before fully thinking of the consequences. Hyperactivity includes an excessive rate of speech and motor activity. Complications of ADHD include academic failure, low self-esteem, poor work performance, substance abuse, criminal justice issues, and social problems. ADHD is predominately due to decreased activity in the frontal lobe. Dopamine and norepinephrine are the main neurotransmitters involved in the pathophysiology of ADHD. Pharmacological treatment of ADHD includes psychostimulants, norepinephrine reuptake inhibitors, α2 agonists, bupropion, and monoamine oxidase inhibitors. The most effective medications are the psychostimulants. Nonpharmacological treatment of ADHD includes coaching, providing structure, academic accommodations, and work accommodations.

Atomoxetine use during a period of FDA actions

CONTEXT

The Food and Drug Administration (FDA) issued a Public Health Advisory entitled "Suicidal Thinking in Children and Adolescents Being Treated with Strattera (Atomoxetine)" on September 29, 2005. At FDA's request, the manufacturer subsequently added a boxed warning to the drug's labeling on November 8, 2005.

OBJECTIVE

To evaluate whether the boxed warning for suicidal thinking in atomoxetine's labeling was associated with a change in the pattern of attention-deficit/hyperactivity disorder (ADHD) medication use.

METHODS

Patients who had an ADHD diagnosis and were prescribed either atomoxetine or stimulants between January 2004 and December 2007 were selected from IMS LifeLink Health Plan Claims database. In this ecologic analysis, the outcome measure is the incident atomoxetine use rate, defined as the proportion of atomoxetine incident users among all initial ADHD pharmacotherapy users. The impact of the boxed warning was evaluated using interrupted time series analysis.

RESULTS

A total of 16,311 patients met the definition of incident ADHD medication users. The incident atomoxetine use rate decreased from January 2004 to September 2005 among all age groups (range, -0.45% to -0.74%); and the rate among adult patients decreased by 11.89% (95% confidence interval, 3.05%-20.74%) from September 2005 to November 2005. No long-term impact was detected.

CONCLUSIONS

Significant decline of the atomoxetine use rate was observed before the boxed warning in all age groups. No significant change was detected in the atomoxetine use rate among targeted children or adolescents after the FDA's boxed warning concerning suicidal thinking.

Pharmacological treatment of attention deficit hyperactivity disorder in children and adolescents: clinical strategies

Attention deficit hyperactivity disorder (ADHD) is a common neurobehavioral disorder of childhood that can result in significant functional impairment, and if not adequately treated can lead to impaired quality of life. Pharmacotherapy is considered the first-line treatment for ADHD in children and adolescents. We review both recent literature and seminal studies regarding the pharmacological treatment of ADHD in children and adolescents. There is ample evidence for the efficacy and safety of both stimulants and non-stimulants in the treatment of ADHD. We review important aspects of evaluation and assessment and discuss first-line pharmacological treatments and as well as when to consider using alternative pharmacological agents. Treatment approaches to manage frequently seen comorbid disorders with ADHD are also covered.

Safety of attention-deficit/hyperactivity disorder medications in children: an intensive pharmacosurveillance monitoring study

OBJECTIVE

Our intensive pharmacosurveillance monitoring program was performed to increase the number of adverse drug reactions (ADRs) recorded in the Italian spontaneous reporting database, and to systematically collect more thorough data about atomoxetine (ATX) and methylphenidate (MPH) safety in the pediatric setting.

METHODS

From September 2007 to October 2010, 1841 youth were enrolled in the Italian Attention- Deficit/Hyperactivity Disorder Register, but we report here on the 76 children from the five Reference Prescription Centers in Campania, an Italian region where we administered our systematic adverse event checklist.

RESULTS

Among our cohort, 68 children received a prescription of ATX and 8 received a prescription of MPH. Most children were male and between 10 and 13 years of age, had a diagnosis of attention-deficit/hyperactivity disorder-combined (ADHD-C) and had learning disability as the main comorbidity. Most ADRs reported to the Italian spontaneous reporting database occurred in patients from Campania. Twenty-five experienced at least 1 ADR for a total of 40 ADRs reported to the Italian drug agency. Most ADRs were common and not serious, and resolved completely. Weight loss was the most frequently reported ADR. Only two ADRs were unexpected and only one was uncommon. Sixteen ADRs resulted in permanent drug withdrawal. Based on the Naranjo algorithm, 25 ADRs were considered "probable" and 15 were considered "possible."

CONCLUSIONS

Although our data provide reassurance of the safety of ATX and MPH, several unexpected or uncommon ADRs (hepatomegaly, suicidal ideation, weight gain, or drug interactions) were identified by our intensive pharmacosurveillance monitoring program. Our results show that an intensive pharmacosurveillance monitoring program that involves pharmacovigilance centers and clinicians can improve the collection of information on drug safety in children.

Pharmacotherapy of pediatric attention-deficit/hyperactivity disorder

This article describes the practical use of available attention-deficit/hyperactivity disorder (ADHD) pharmacotherapies, their formulations and durations of action, and the extent of Food and Drug Administration approvals. It provides data on short-term and long-term safety of these medications, their use in ADHD with comorbid conditions, and strategies for formulating individualized, effective, and well-tolerated pharmacotherapy treatment plans. A clinical vignette focusing on a male child with ADHD is presented. Summaries are presented of ADHD pharmacotherapies and Food and Drug Administration approval status, atomoxetine and stimulant comparator trials, adverse effects and ADHD pharmacotherapy, and delivery system and duration of effect.

Off-label use of atomoxetine in adults: is it safe?

Atomoxetine has been approved for the treatment of attention deficit/hyperactivity disorder in both adults and children. However, it is also being examined for several off-label uses in adults including mood disorders, eating disorders, cognitive dysfunction, and the treatment of addictions. Prior to such use it is important to examine the reported adverse events to see if this represents an appropriate level of risk. This is particularly important in the light of recent warnings from several regulatory bodies about an increase in blood pressure in a significant percentage of patients taking atomoxetine. To understand the risks a literature review was performed, and which identified the following potential problems. The first is that this drug should not be given in patients with known cardiovascular problems, and that all adult patients who receive atomoxetine should be monitored for changes in blood pressure throughout treatment. Secondly, there are several clinical situations in which atomoxetine should be closely monitored, or avoided, including patients who have a history or risk of narrow angle glaucoma, epileptic seizures, Tourette's syndrome, a history of urinary outflow obstruction, or who are pregnant or lactating. In conclusion, the current literature suggests that atomoxetine can be safely used off-label provided the above precautions are taken.

The evidence-based pharmacological treatment of paediatric ADHD

Attention deficit hyperactivity disorder (ADHD) is common in children, adolescents, and adults, with extensive research establishing it as a valid neurobiological disorder. Without intervention, ADHD can result in significant impairment throughout the lifespan for the individuals it afflicts. Fortunately, multiple evidence-based options are available for the treatment of ADHD, including several efficacious pharmacotherapies. The role of medication, including stimulants as well as non-stimulants, is well-documented by an extensive body of literature. Although there may be less enthusiasm for behavioural and other psychosocial interventions as stand-alone treatments for moderate to severe ADHD, they are recommended as first-line treatment for ADHD management in preschool-aged children, for those patients with mild symptoms, and as an adjunct to medication in patients with comorbid disorders or suboptimal responses to pharmacotherapy. When planning treatment for individuals with ADHD, the potential risks associated with the available interventions must be carefully balanced against the risks of not treating, or not treating adequately. The treatment plan must also include ongoing re-assessment of the effectiveness of and the need for continued therapy. Recent practice parameters provide further specific guidance for the evidence-based assessment and treatment of children and adolescents with ADHD.

Efficacy and Safety of Atomoxetine in the Treatment of Children and Adolescents with Attention Deficit Hyperactivity Disorder

Several non-stimulant medications have been used in the treatment of attention deficit hyperactivity disorder (ADHD). Atomoxetine, was introduced in 2002. The safety and efficacy of atomoxetine in the treatment of ADHD for children, adolescents, and adults has been evaluated in over 4000 patients in randomized controlled studies and double blinded studies as well as in recent large longitudinal studies. This paper provides an updated summary of the literature on atomoxetine, particularly in relation to findings on the short- and long-term safety of atomoxetine in children and adolescents arising from recent large longitudinal cohort studies. Information is presented about the efficacy, safety, and tolerability of this medication.

Which psychotropic medications induce hepatotoxicity?

OBJECTIVE

Safe prescribing practices to minimize pharmaceutically induced liver damage or worsening of preexisting conditions require knowledge about medicines with hepatotoxic potential. This paper reviews psychotropic medications and their effects on the liver.

METHODS

A MEDLINE search was performed utilizing the phrase "drug-induced liver injury" with various categories of psychiatric drugs. Only articles written in English were utilized.

RESULTS

Hepatotoxicity can be acute or chronic in nature. Medication discontinuation is necessary in acute forms, while close monitoring is required in milder forms of medication-induced chronic liver damage. Nefazodone, pemoline and/or tacrine are the highest offenders. Carbamazepine and valproate products (e.g., divalproex) can lead to this adverse event and should be avoided in patients with liver disease, persons with alcohol misuse or those consuming high doses of acetaminophen.

CONCLUSION

Knowing the risk levels associated with various medicines is important; prescribing multiple drugs with hepatotoxic effects should be avoided. One should educate patients about early warning signs of liver injury. Always provide clinical and laboratory monitoring before and during the use of hepatotoxic drugs. Clinical features and laboratory results govern medication prescribing with ongoing risk-to-benefit ratio assessment during pharmacotherapy.

Achieving remission as a routine goal of pharmacotherapy in attention-deficit hyperactivity disorder

Remission should be the goal of attention-deficit hyperactivity disorder (ADHD) treatment. However, there is no universally accepted definition of remission in ADHD, although clinical studies use a number of criteria. This article examines current research into the concept of remission in ADHD by reviewing the literature for definition and achievement of remission in children and adults with ADHD. Results demonstrate that the concept of remission in ADHD has been proposed by several study groups, using thresholds of validated rating scales to indicate syndromic, symptomatic and functional remission. Several studies have demonstrated the achievement of remission in ADHD children utilizing methylphenidate delivered by an osmotic, controlled-release formulation (OROS®) and atomoxetine. However, none has defined a time period over which these criteria must be met for an individual with ADHD to be considered 'in remission'. Standardized remission criteria in ADHD will provide a tool for assessing the effectiveness of treatments for ADHD, and raise treatment standards.

The occurrence of adverse drug reactions reported for attention deficit hyperactivity disorder (ADHD) medications in the pediatric population: a qualitative review of empirical studies

BACKGROUND

To review empirical studies of adverse drug reactions (ADRs) reported to be associated with the use of medications generally licensed for treatment of attention deficit hyperactivity disorder (ADHD) symptoms in the pediatric population.

METHODS

PubMed, Embase, and PsycINFO(®) databases were searched from origin until June 2011. Studies reporting ADRs from amphetamine derivates, atomoxetine, methylphenidate, and modafinil in children from birth to age 17 were included. Information about ADR reporting rates, age and gender of the child, type, and seriousness of ADRs, setting, study design, ADR assessors, authors, and funding sources were extracted.

RESULTS

The review identified 43 studies reporting ADRs associated with medicines for treatment of ADHD in clinical studies covering approximately 7000 children, the majority of 6- to 12-year-old boys, and particularly in the United States of America (USA). The most frequently reported ADRs were decrease in appetite, gastrointestinal pain, and headache. There were wide variations in reported ADR occurrence between studies of similar design, setting, included population, and type of medication. Reported ADRs were primarily assessed by the children/their parents, and very few ADRs were rated as being serious. A large number of children dropped out of studies due to serious ADRs, and therefore, the actual number of serious ADRs from use of psychostimulants is probably higher. A large number of studies were conducted by the same groups of authors and sponsored by the pharmaceutical companies manufacturing the respective medications.

CONCLUSION

Reported ADRs from use of psychostimulants in children were found in clinical trials of short duration. Since ADHD medications are prescribed for long-term treatment, there is a need for long-term safety studies. The pharmaceutical companies should make all information about ADRs reported for these medications accessible to the public, and further studies are needed on the impact of the link between researchers and the manufacturers of the respective products.

ADHD medication use, adherence, persistence and cost among Texas Medicaid children

OBJECTIVES

(1) Describe ADHD medication use, adherence and persistence. (2) Determine factors (e.g., medication type, demographics, concomitant medication use) associated with ADHD medication adherence and persistence. (3) Compare ADHD medication costs.

METHODS

Continuously enrolled Texas Medicaid children (3-18 years) with ≥ 2 ADHD prescription claims (July 2002-December 2008) were included. Prescription claims were grouped by medication type (i.e., immediate-release, extended-release, prodrug, non-stimulant); medication class (i.e., stimulant, non-stimulant); and duration of action (i.e., long-acting, short-acting). Adherence, using medication possession ratio, was measured continuously and dichotomously (80% cut-off). Persistence was days of continuous therapy without a 30-day gap and medication costs were reimbursement amount paid to dispensing pharmacies.

RESULTS

The study sample (n = 62,789) was primarily 6-12 years (61.7%) and male (69.2%). The majority of the subjects were prescribed extended-release agents (70.3%), stimulant agents (86.4%), and long-acting agents (84.5%). Adherence and persistence (adherence mean ± SD; adherence dichotomous; persistence mean ± SD) varied among medication type and was highest for non-stimulants (52.5 ± 30.9; 25.8%; 153.3 ± 124.3), followed by extended-release stimulants (52.1 ± 30.2; 24.1%; 143.7 ± 120.8), prodrug stimulants (47.6 ± 30.9; 21.1%; 113.3 ± 100.5) and immediate-release stimulants (37.2 ± 27.1; 9.8%; 95.4 ± 92.6). Logistic regression showed immediate-release stimulant users were 67% less adherent than non-stimulant users (p < 0.0001) and linear regression showed immediate-release, extended-release and long-acting users (p < 0.0001) were significantly less persistent than non-stimulant users. Females, increase in total number of medications, and comorbid medications were associated with better adherence and persistence. Non-stimulant agents ($4.04 ± $2.15) had the highest mean medication cost per patient per day and immediate-release stimulants had the lowest ($1.24 ± $0.97).

CONCLUSIONS

ADHD medication adherence and persistence was suboptimal. Although there was no difference in adherence between long-acting stimulant and non-stimulant users, non-stimulant users were more persistent compared to stimulant users. This study was limited due to the use of retrospective prescription claims data, which cannot capture actual patient use patterns, ICD-9 diagnoses, family history and support, or side effect profiles. Because ADHD can be effectively treated with pharmacotherapy, providers should be proactive in identifying patients with poor adherence and intervene to address barriers to medication adherence and persistence.

Attention deficit hyperactivity disorder in adults

OBJECTIVE

To examine available literature regarding attention deficit hyperactivity disorder (ADHD) in adults.

METHODS

An electronic literature search of peer-reviewed English language articles using MEDLINE (without time limits) was undertaken.

RESULTS

Symptoms of ADHD in adults exert a substantial negative impact on daily life, including work, social life and relationships. Co-morbidities are common, further impairing quality of life. Diagnosis of adult ADHD can be difficult, as current criteria require evidence of symptom onset before the age of 7 years and impact on activities typically undertaken by children. Drug therapy is the first-line treatment for adult ADHD, particularly stimulant medication. However, methylphenidate (MPH) immediate-release tablets require three or more times daily dosing, which can impact on compliance, while demonstrating a loss of symptomatic benefit later in the day. Extended-release preparations of MPH, mixed amphetamine salts and dexamphetamine can provide symptom control for 6-12 h and the non-stimulant atomoxetine has demonstrated benefit in reducing ADHD symptoms. These therapies are generally well tolerated, but may be associated with adverse effects on the cardiovascular system, which need to be further assessed in controlled clinical trials. Psychological therapy may be beneficial in adults who continue to experience clinically significant symptoms while receiving pharmacotherapy.

CONCLUSION

Further research in all areas of adult ADHD is urgently needed.

Eosinophilic hepatitis in an adolescent during lisdexamfetamine dimesylate treatment for ADHD

We describe here the case of an adolescent who developed eosinophilic hepatitis during treatment for attention-deficit/hyperactivity disorder with lisdexamfetamine dimesylate (Vyvanse [Shire US Inc, Wayne, PA]). A 14-year-old boy presented to his primary care provider with abdominal pain and worsening jaundice. A diagnosis of hepatitis was made with biochemical markers, but evaluation failed to provide an etiology. Worsening hepatitis prompted hospitalization and initiation of steroids for presumed autoimmune hepatitis. A subsequent liver biopsy showed evidence of eosinophilic hepatitis. Known causes of eosinophilic hepatitis were ruled out, and a presumptive diagnosis of reaction to lisdexamfetamine dimesylate was made. Discontinuation of the medication led to resolution of the hepatitis and normalization of the liver biopsy. To our knowledge, this is the first report of hepatic injury attributed to lisdexamfetamine dimesylate.

Spotlight on atomoxetine in attention-deficit hyperactivity disorder in children and adolescents

Atomoxetine (Strattera) is a selective noradrenaline (norepinephrine) reuptake inhibitor that is not classified as a stimulant, and is indicated for use in patients with attention-deficit hyperactivity disorder (ADHD). Atomoxetine is effective and generally well tolerated. It is significantly more effective than placebo and standard current therapy and does not differ significantly from, or is noninferior to, immediate-release methylphenidate; however, it is significantly less effective than the extended-release methylphenidate formulation OROS methylphenidate (hereafter referred to as osmotically released methylphenidate) and extended-release mixed amfetamine salts. Atomoxetine can be administered either as a single daily dose or split into two evenly divided doses, has a negligible risk of abuse or misuse and is not a controlled substance in the US. Atomoxetine is particularly useful for patients at risk of substance abuse, as well as those who have co-morbid anxiety or tics, or who do not wish to take a controlled substance. Thus, atomoxetine is a useful option in the treatment of ADHD in children and adolescents.

An open study of adjunct OROS-methylphenidate in children who are atomoxetine partial responders: II. Tolerability and pharmacokinetics

OBJECTIVE

The aim of this study was to evaluate the tolerability of adding OROS methylphenidate (MPH) to children who are partial responders to atomoxetine (ATMX) in the treatment of attention-deficit/hyperactivity disorder (ADHD).

METHODS

This was a two-phase, 7-week, open study in children aged 6-17 years. Phase 1 initiated ATMX for a minimum of 4 weeks. Phase 2 entered partial responders to ATMX and added OROS MPH to their regimen. Safety was assessed using blood pressure and heart rate measurements, electrocardiogram readings, AEs, laboratories, and ATMX levels.

RESULTS

Fifty subjects who were partial responders to ATMX received the combination therapy, with 41 subjects completing the entire protocol. As reported elsewhere (Wilens et al., 2009 ), OROS MPH added to partial responders of ATMX was accompanied by a 40% reduction in the ADHD rating scale score and improvements in executive functioning. However, the combination of ATMX plus OROS MPH was associated with greater rates of insomnia, irritability, and loss of appetite compared to ATMX alone. A small significant increase in diastolic blood pressure was observed during adjunctive OROS MPH, with no clinically meaningful changes in electrocardiogram (ECG) parameters during the study. ATMX levels and liver function tests did not significantly change during the combination treatment.

CONCLUSION

Adjunct OROS MPH in ATMX partial responders yielded an additive adverse effect burden in this short-term study. Further controlled research with larger samples of children is warranted.

Drug-induced liver injury: what was new in 2008?

BACKGROUND

Given the number of publications appearing annually regarding drug-induced liver injury (DILI), there remains a need to concisely summarize each year's new crop of case series and reports as well as the advances in mechanisms of liver injury and in the field of pharmacogenomics relating to DILI.

OBJECTIVE

To present an up-to-date review of the past year's most important clinical studies and reports of DILI, placing them into context of previous publications.

METHODS

A Medline search was conducted of all manuscripts appearing in the fields "hepatotoxicity" and "drug-induced liver injury" during the calendar year 2008. The most clinically relevant English language case reports and studies exploring mechanisms and risk factors for DILI were then chosen for review, and supplemented with older literature where appropriate.

CONCLUSIONS

As in past years, 2008 was replete with publications dealing with virtually all facets of DILI, including updated incidence and prevalence data, as well as the latest information regarding mechanisms of liver injury. Data from the first 300 patients in the National Institute of Health-sponsored DILI Network registry of > 100 non-acetaminophen causes were presented. Antimicrobials and CNS drugs were responsible for > 60% of cases, with herbals and dietary supplements being increasingly reported. Identification of genetic predispositions to DILI is coming of age with the FDA calling for the testing of human leukocyte antigen B(*)5701 before the use of abacavir to reduce the risk of hypersensitivity reactions. Several groups emphasized the pitfalls in utilizing Roussel Uclaf Causality Assessment Method and other causality assessment methodologies, and an updated review appeared on the use of potentially hepatotoxic medications in patients with underlying liver disease.

Use of atomoxetine in patients with attention-deficit hyperactivity disorder and co-morbid conditions

Attention-deficit hyperactivity disorder (ADHD) is one of the most common neurobehavioural disorders in children. It has been shown that as many as 85% of patients with ADHD have at least one psychiatric co-morbidity, and approximately 60% have at least two. Atomoxetine is a specific, noradrenergic reuptake inhibitor that provides an effective treatment option for patients with ADHD and co-morbid conditions. The efficacy of atomoxetine in treating ADHD appears to be unaffected by the presence of co-morbid conditions. Therapy with atomoxetine has been associated with statistically significant improvements in symptoms of oppositional defiant disorder in most, but not all, studies. Limited data suggest this agent may have potential in improving co-occurring symptoms of anxiety and may be useful in patients with co-morbid conditions such as tics or Tourette's syndrome. The tolerability profile of atomoxetine in patients with ADHD and co-morbid conditions was similar to that of patients with uncomplicated ADHD. Atomoxetine was well tolerated, with adverse events generally mild and transient; the most frequent adverse events in patients with ADHD included abdominal pain, decreased appetite, nausea and vomiting. The favourable safety and efficacy profile of atomoxetine makes it a promising treatment for patients with ADHD and associated co-morbidities.

Atomoxetine: a review of its use in attention-deficit hyperactivity disorder in children and adolescents

Atomoxetine (Strattera(R)) is a selective norepinephrine (noradrenaline) reuptake inhibitor that is not classified as a stimulant, and is indicated for use in patients with attention-deficit hyperactivity disorder (ADHD). Atomoxetine is effective and generally well tolerated. It is significantly more effective than placebo and standard current therapy and does not differ significantly from or is noninferior to immediate-release methylphenidate; however, it is significantly less effective than the extended-release methylphenidate formulation OROS(R) methylphenidate (hereafter referred to as osmotically released methylphenidate) and extended-release mixed amfetamine salts. Atomoxetine can be administered either as a single daily dose or split into two evenly divided doses, has a negligible risk of abuse or misuse, and is not a controlled substance in the US. Atomoxetine is particularly useful for patients at risk of substance abuse, as well as those who have co-morbid anxiety or tics, or who do not wish to take a controlled substance. Thus, atomoxetine is a useful option in the treatment of ADHD in children and adolescents. The mechanism of action of atomoxetine is unclear, but is thought to be related to its selective inhibition of presynaptic norepinephrine reuptake in the prefrontal cortex. Atomoxetine has a high affinity and selectivity for norepinephrine transporters, but little or no affinity for various neurotransmitter receptors. Atomoxetine has a demonstrated ability to selectively inhibit norepinephrine uptake in humans and animals, and studies have shown that it preferentially binds to areas of known high distribution of noradrenergic neurons, such as the fronto-cortical subsystem. Atomoxetine was generally associated with statistically, but not clinically, significant increases in both heart rate and blood pressure in pediatric patients with ADHD. While there was an initial loss in expected height and weight among atomoxetine recipients, this eventually returned to normal in the longer term. Data suggest that atomoxetine is unlikely to have any abuse potential. Atomoxetine appeared less likely than methylphenidate to exacerbate disordered sleep in pediatric patients with ADHD. Atomoxetine is rapidly absorbed, and demonstrates dose-proportional increases in plasma exposure. It undergoes extensive biotransformation, which is affected by poor metabolism by cytochrome P450 (CYP) 2D6 in a small percentage of the population; these patients have greater exposure to and slower elimination of atomoxetine than extensive metabolizers. Patients with hepatic insufficiency show an increase in atomoxetine exposure. CYP2D6 inhibitors, such as paroxetine, are associated with changes in atomoxetine pharmacokinetics similar to those observed among poor CYP2D6 metabolizers. Once- or twice-daily atomoxetine was effective in the short-term treatment of ADHD in children and adolescents, as observed in several well designed placebo-controlled trials. Atomoxetine also demonstrated efficacy in the longer term treatment of these patients. A single morning dose was shown to be effective into the evening, and discontinuation of atomoxetine was not associated with symptom rebound. Atomoxetine efficacy did not appear to differ between children and adolescents. Stimulant-naive patients also responded well to atomoxetine treatment. Atomoxetine did not differ significantly from or was noninferior to immediate-release methylphenidate in children and adolescents with ADHD with regard to efficacy, and was significantly more effective than standard current therapy (any combination of medicines [excluding atomoxetine] and/or behavioral counseling, or no treatment). However, atomoxetine was significantly less effective than osmotically released methylphenidate and extended-release mixed amfetamine salts. The efficacy of atomoxetine did not appear to be affected by the presence of co-morbid disorders, and symptoms of the co-morbid disorders were not affected or were improved by atomoxetine administration. Health-related quality of life (HR-QOL) appeared to be positively affected by atomoxetine in both short- and long-term studies; atomoxetine also improved HR-QOL to a greater extent than standard current therapy. Atomoxetine was generally well tolerated in children and adolescents with ADHD. Common adverse events included headache, abdominal pain, decreased appetite, vomiting, somnolence, and nausea. The majority of adverse events were mild or moderate; there was a very low incidence of serious adverse events. Few patients discontinued atomoxetine treatment because of adverse events. Atomoxetine discontinuation appeared to be well tolerated, with a low incidence of discontinuation-emergent adverse events. Atomoxetine appeared better tolerated among extensive CYP2D6 metabolizers than among poor metabolizers. Slight differences were evident in the adverse event profiles of atomoxetine and stimulants, both immediate- and extended-release. Somnolence appeared more common among atomoxetine recipients and insomnia appeared more common among stimulant recipients. A black-box warning for suicidal ideation has been published in the US prescribing information, based on findings from a meta-analysis showing that atomoxetine is associated with a significantly higher incidence of suicidal ideation than placebo. Rarely, atomoxetine may also be associated with serious liver injury; postmarketing data show that three patients have had liver-related adverse events deemed probably related to atomoxetine treatment. Treatment algorithms involving the initial use of atomoxetine appear cost effective versus algorithms involving initial methylphenidate (immediate- or extended-release), dexamfetamine, tricyclic antidepressants, or no treatment in stimulant-naive, -failed, and -contraindicated children and adolescents with ADHD. The incremental cost per quality-adjusted life-year is below commonly accepted cost-effectiveness thresholds, as shown in several Markov model analyses conducted from the perspective of various European countries, with a time horizon of 1 year.

Assessing the value of atomoxetine in treating children and adolescents with ADHD in the UK

BACKGROUND

Economic evaluation of healthcare technologies is becoming increasingly relevant, enabling decision makers to assess and compare treatments within the context of costs and outcomes. Moreover, it is increasingly important for clinicians and prescribers to have some understanding of economic evaluation. For attention-deficit/hyperactivity disorder (ADHD), economic evaluations have largely focused on pharmacotherapy, and results indicate that such treatments are cost-effective compared with other interventions.

AIMS

This review provides an overview of ADHD, its consequences and pharmacotherapy; describes the principles of health economic analysis, health-related quality of life (HRQL) and a cost-effectiveness model of atomoxetine for ADHD treatment; and outlines guidance from the National Institute for Health and Clinical Excellence on ADHD pharmacotherapy.

METHODS

The cost-effectiveness of atomoxetine for children with ADHD in the UK was compared with treatment alternatives using an economic model with Markov processes. The model evaluated atomoxetine in five patient subgroups according to treatment history and comorbidities precluding stimulants. Incremental cost per quality-adjusted life-year (QALY) was calculated and compared between treatment algorithms. The Markov process incorporated 18 health states, representing a range of outcomes across the treatments. Utility values were derived from a survey of 83 parents of children with ADHD, and treatment efficacy and safety were based on a review of controlled clinical trials and literature, and validated by international experts. Costs and outcomes were estimated using Monte Carlo simulation over 1-year.

RESULTS

Atomoxetine was a cost-effective treatment across the whole ADHD population, with incremental cost-effectiveness ratios ranging from pound 11,500 to pound 15,900 per QALY, compared with alternative pharmacotherapies, which are within UK and rest of Europe acceptability limits. Higher utility values achieved treating ADHD with atomoxetine, compensate for the relatively higher acquisition cost compared with stimulants.

CONCLUSIONS

Atomoxetine is cost-effective and may have advantages over stimulants, including benefits to HRQL and no abuse liability and is the only treatment in the UK licensed for continued treatment into adulthood in adolescents who have shown a response from treatment.