An open-label trial of tomoxetine in pediatric attention deficit hyperactivity disorder

Therapeutic drug monitoring of atomoxetine in children and adolescents with attention-deficit/ hyperactivity disorder: a naturalistic study

The selective norepinephrine reuptake inhibitor atomoxetine is potentially among the first-line pharmacotherapy options for ADHD. Therapeutic drug monitoring (TDM) with the quantification and interpretation of atomoxetine serum concentrations is used to determine an individual dose followed by an optimal effectiveness and minimal side effects. The aim of this retrospective pharmacokinetic–pharmacodynamic analysis was to derive age-appropriate recommendations for the implementation of TDM to improve the efficacy and tolerability of atomoxetine in children and adolescents. Using the analytical method of high-performance liquid chromatography with UV detection, 94 serum concentrations of 74 patients between 6 and 21 years of age were determined. Therapeutic effectiveness and side effects were evaluated according to the categories “low”, “moderate”, and “significant”. As part of TDM, a time interval with maximum concentrations of 1–3 h after the administration of atomoxetine was determined for blood sampling. In this time interval, a significant correlation between the weight-normalized dose and the serum concentrations was found. The efficacy as well as the tolerability proved to be mainly moderate or significant. A preliminary therapeutic reference range was between 100 and 400 ng/ml. Naturalistic studies have limitations. Therefore, and due to a limited study population, the results have to be regarded as preliminary observations that must be confirmed in further studies. The preliminary therapeutic reference range for children and adolescents proved to be narrower than the reference range for adult patients. However, due to good efficacy and tolerability an exact reference range remained difficult to determine.

Atomoxetine treatment for children and adolescents with Attention-Deficit/Hyperactivity Disorder (ADHD): a comprehensive meta-analysis of outcomes on parent-rated core symptomatology

Attention-Deficit/Hyperactivity Disorder (ADHD) impacts a significant number of children and adolescents and often leads to deleterious functional impairment. Psychostimulant medication has historically been the first line of pharmacological intervention, though recent years have seen greater attention paid to non-stimulant alternatives. The objective of the present study was to conduct the most comprehensive meta-analysis to date evaluating the efficacy of atomoxetine in reducing core symptomatology of ADHD according to parent report. Selection criteria were applied, and studies were located by searching electronic databases, review of reference sections, and contact with expert researchers; article searching began on 10/01/2013, and the final search was conducted on 09/01/2014. A total of 42 studies met inclusion criteria-33 with control groups and 9 without-for a total sample of 8398 individuals. For those receiving atomoxetine, the summary pre-post (e.g., standardized mean gain) effect size estimate was 1.37 (95% CI [1.24, 1.51], p < .001); atomoxetine was found to statistically significantly outperform control conditions overall (Z = 4.07, p < .001), though results differed by the type of control group; for instance, when comparing atomoxetine to alternative medications as controls, significant differences were no longer present. The non-stimulant atomoxetine led to significant improvement in core ADHD symptomatology and should be considered as a viable pharmacological treatment option for ADHD.

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.

The efficacy of atomoxetine for the treatment of children and adolescents with attention-deficit/hyperactivity disorder: a comprehensive review of over a decade of clinical research

Atomoxetine was first licensed to treat attention-deficit/hyperactivity disorder (ADHD) in children and adolescents in the US in 2002. The aim of this paper is to comprehensively review subsequent publications addressing the efficacy of atomoxetine in 6- to 18-year-olds with ADHD. We identified 125 eligible papers using a predefined search strategy. Overall, these papers demonstrate that atomoxetine is an effective treatment for the core ADHD symptoms (effect sizes 0.6-1.3, vs. placebo, at 6-18 weeks), and improves functional outcomes and quality of life, in various pediatric populations with ADHD (i.e., males/females, patients with co-morbidities, children/adolescents, and with/without prior exposure to other ADHD medications). Initial responses to atomoxetine may be apparent within 1 week of treatment, but can take longer (median 23 days in a 6-week study; n=72). Responses often build gradually over time, and may not be robust until after 3 months. A pooled analysis of six randomized placebo-controlled trials (n=618) indicated that responses at 4 weeks may predict response at 6-9 weeks, although another pooled analysis of open-label data (n=338) suggests that the probability of a robust response to atomoxetine [≥40% decrease in ADHD-Rating Scale (ADHD-RS) scores] may continue to increase beyond 6-9 weeks. Atomoxetine may demonstrate similar efficacy to methylphenidate, particularly immediate-release methylphenidate, although randomized controlled trials are generally limited by short durations (3-12 weeks). In conclusion, notwithstanding these positive findings, before initiating treatment with atomoxetine, it is important that the clinician sets appropriate expectations for the patient and their family with regard to the likelihood of a gradual response, which often builds over time.

Toward quality care in ADHD: defining the goals of treatment

OBJECTIVE

Therapeutic goals for chronic mental disorders like major depressive disorder (MDD) and schizophrenia have evolved in parallel with the growing medical knowledge about the course and treatment of these disorders. Although the knowledge base regarding the clinical course of ADHD, a chronic psychiatric disorder, has evolved beyond symptomatic improvement and short-term treatment response, long-term goals, such as functional remission, have not yet been clearly defined.

METHOD

A PubMed literature search was conducted to investigate the therapeutic goals of pharmacologic treatment referenced in the published literature from January 1998 through February 2010 using the following commonly used ADHD treatments as keywords: amphetamine, methylphenidate, atomoxetine, lisdexamfetamine, guanfacine, and clonidine. This search was then combined with an additional search that included the following outcome keywords: remission, relapse, remit, response, normal, normalization, recovery, and effectiveness.

RESULTS

Our search identified 102 publications. The majority (88.2% [90/102]) of these contained predefined criteria for treatment response. Predefined criteria for normalization and remission and/or relapse were presented in 4.9% (5/102), 12.7% (13/102), and 3.9% (4/102) of publications, respectively. There was a lack of consistency between the instruments used to measure outcomes as well as the criteria used to define treatment response, normalization, and remission as well as relapse.

CONCLUSION

The therapeutic goals in treating ADHD should address optimal treatment outcomes that go beyond modest reductions of ADHD symptoms to include syndromatic, symptomatic, and functional remission. Future work should focus on reliable and valid tools to measure these outcomes in the clinical trial setting.

Efficacy and safety of extended-release guanfacine hydrochloride in children and adolescents with attention-deficit/hyperactivity disorder: a randomized, controlled, phase III trial

Guanfacine extended-release (GXR), a selective α2A-adrenergic agonist, is a non-stimulant treatment for attention-deficit/hyperactivity disorder (ADHD). This study assessed the efficacy (symptoms and function) and safety of dose-optimized GXR compared with placebo in children and adolescents with ADHD. An atomoxetine (ATX) arm was included to provide reference data against placebo. Patients (6-17 years) were randomized at baseline to dose-optimized GXR (0.05-0.12mg/kg/day - 6-12 years: 1-4mg/day; 13-17 years: 1-7mg/day), ATX (10-100mg/day) or placebo for 4 or 7 weeks. The primary efficacy measure was change from baseline in ADHD Rating Scale version IV (ADHD-RS-IV). Key secondary measures were Clinical Global Impression-Improvement (CGI-I) and the Weiss Functional Impairment Rating Scale-Parent Report (WFIRS-P; learning and school, and family domains). Safety assessments included treatment-emergent adverse events (TEAEs), electrocardiograms and vital signs. A total of 272 (80.5%) patients from Europe, the USA and Canada completed the study. Significant differences were observed in least squares mean change from baseline in ADHD-RS-IV total score (placebo-adjusted differences) (GXR: [-8.9, p<0.001]; ATX: [-3.8, p<0.05]), the difference from placebo in the percentage of patients showing improvement (1 ['very much improved'] or 2 ['much improved']) for CGI-I (GXR: [23.7, p<0.001]; ATX: [12.1, p<0.05]), WFIRS-P learning and school domain (GXR: [-0.22, p<0.01]; ATX: [-0.16, p<0.05]) and WFIRS-P family domain (GXR: [-0.21, p<0.01]; ATX: [-0.09, p=0.242]). Most common TEAEs for GXR were somnolence, headache and fatigue; 70.1% of GXR subjects reported mild-to-moderate TEAEs. GXR was effective and well tolerated in children and adolescents with ADHD.

A cohort study of the risk of seizures in a pediatric population treated with atomoxetine or stimulant medications

PURPOSE

Stimulant medications used for treating attention deficit hyperactivity disorder (ADHD) can be associated with an increased risk of seizures. Atomoxetine is a non-stimulant medication approved for treating ADHD. This retrospective cohort analysis evaluated risk of seizures among pediatric patients naïve to ADHD medication therapy, with exposure to atomoxetine relative to stimulant medications.

METHODS

Among members of a large US health plan from 1/1/2003 to 12/31/2006, aged 6-17 years, we identified initiators of atomoxetine or stimulants with no evidence of prior study drug use. We created study cohorts using propensity score matching within 6-month calendar blocks. The outcome was a seizure event in the 6-month follow-up period verified through medical record review. Relative risks (RR) based on current use of each study drug adjusted for baseline covariates were calculated using Poisson regression. We estimated hazard ratios from Cox proportional hazards models for the comparison of atomoxetine to stimulants based on initial cohort assignment.

RESULTS

We matched 13,398 initiators of atomoxetine to 13,322 initiators of stimulants. We identified 97 seizure events. After adjustment, current atomoxetine therapy was associated with a non-statistically significant 28% lower risk of seizure compared to current stimulant therapy (RR 0.72; 95%CI 0.37, 1.38). The adjusted RR of seizure with atomoxetine compared to stimulants based on initial cohort assignment was 0.90 (95%CI 0.54, 1.49).

CONCLUSIONS

These results do not support an increase in the risk of seizure with atomoxetine therapy. The risk of seizure was not significantly different between pediatric patients taking atomoxetine compared with those taking stimulants.

A randomized, open-label assessment of response to various doses of atomoxetine in korean pediatric outpatients with attention-deficit/hyperactivity disorder

OBJECTIVE

This multicenter, randomized, open-label, parallel trial aimed to provide a detailed dose-response profile for atomoxetine in Korean pediatric outpatients with attention-deficit/hyperactivity disorder (ADHD).

METHODS

Male and female outpatients aged 6-18 years with ADHD meeting symptom severity criteria of 1.5 standard deviations above age and gender norms on the ADHD Rating Scale-IV-Parent: Investigator-Administered and Scored (ADHDRS-IV-Parent: Inv), and a Clinical Global Impression-ADHD-Severity score ≥4 were randomized to atomoxetine (mg/kg/day) 0.2 fixed, 0.5 fixed or 0.5 (7 days), 0.8 (7 days) then 1.2 for 28 days. The primary efficacy measure was change in ADHDRS-IV-Parent: Inv total score after 6 weeks of atomoxetine treatment.

RESULTS

Of 153 randomized patients, 83.7% were male and mean age was 9.8 (SD±2.4) years. The completion rate was 86.9%. A graded dose response was apparent with mean change in ADHDRS-IV-Parent: Inv total scores of -9.6, -12.3 and -14.5 with atomoxetine 0.2, 0.5 and 1.2 mg/kg/day, respectively (p=0.024 - F-test). Moreover, a greater reduction in ADHD symptoms, as assessed by mean change from baseline to endpoint CGI-S and mean CGI-ADHD-Improvement at endpoint, was also observed with increasing atomoxetine dose. More patients receiving atomoxetine 1.2 mg/kg/day reported ≥1 treatment-emergent adverse event/s (58.3%) compared with 0.5 (40.7%; p=0.11) or 0.2 mg/kg/day (29.4%; p=0.005). These were generally mild to moderate.

CONCLUSION

Atomoxetine was found to be safe and well tolerated at all doses administered in Korean pediatric ADHD patients, and 1.2 mg/kg/day was an efficacious dose in this population.

Psychopharmacological interventions

Currently stimulants and atomoxetine are the most established treatments for attention deficit hyperactivity disorder (ADHD); more than 170 controlled studies with more than 9000 subjects have documented their efficacy in 50% to 70% of subjects. Although the stimulant medications tend to show a dose-related improvement in ADHD symptoms, atomoxetine is generally dosed based on weight. The literature clearly documents that stimulants improve not only abnormal behaviors of ADHD but also self-esteem, cognition, and social and family functioning. However, efficacy varies with age and psychiatric comorbidities. Although most of the existing studies are brief, an increasing number of long-term studies have documented persistent response up to 1 and 2 years. Recent studies are extending the knowledge of treatment to younger and older subjects, women, and ethnic minorities. Cognitive and cognitive/behaviorally based psychotherapies combined with medication may play a role in treating behavioral and organizational issues and comorbid psychopathology.

Efficacy and safety of atomoxetine for attention-deficit/hyperactivity disorder in children and adolescents-meta-analysis and meta-regression analysis

OBJECTIVES

The objective of this study was to evaluate the efficacy and safety of atomoxetine in children and adolescents.

MATERIALS AND METHODS

We searched for studies published between 1985 and 2006 through Medline, PubMed, PsychInfo and Cochrane Central Register of Controlled Trials (CENTRAL 2006 Issue 3) using keywords related to atomoxetine and attention-deficit/hyperactivity disorder (ADHD) and scanned though reference lists. We included nine randomized placebo-controlled trials (atomoxetine:placebo = 1,150:678).

RESULTS

Atomoxetine was superior (p < 0.01) to placebo in reducing ADHD symptoms across different scales (Attention-Deficit/Hyperactivity Disorder Rating Scale-IV, Conners' Parent and Teacher Rating Scales-Revised:Short Form, Clinical Global Impression-Severity) rated by different raters (parent, teacher, clinician). The number-needed-to-treat (NNTs) for treatment response and relapse prevention were 3.43 (95% CI, 2.79-4.45) and 10.30 (95% CI, 5.89-40.62), respectively. High baseline ADHD symptoms (p = 0.02) was associated with greater reduction in ADHD symptoms, whereas male gender (p = 0.02), comorbid oppositional defiant disorder (ODD) status (p = 0.01) and ADHD hyperactive/impulsive subtype (p = 0.01) were associated with smaller reductions. The commonest adverse events were gastrointestinal [appetite decrease, number-needed-to-harm (NNH) = 8.81; abdominal pain, NNH = 22.48; vomiting, NNH = 29.96; dyspepsia, NNH = 49.38] and sleep related (somnolence, NNH = 19.41). Young age (p = 0.03) and high baseline hyperactive/impulsive symptoms (p < 0.01) were associated with more adverse events, whereas ADHD inattentive subtype (p = 0.04) was associated with less adverse events. Quality of life using Child Health Questionnaire (CHQ) improved (p < 0.01) with atomoxetine treatment. Both ADHD and ODD symptoms (p < 0.01) were reduced in comorbid ADHD+ODD, and ODD status was not associated with more adverse events. Efficacy and side effects were not altered by comorbid general anxiety disorder or major depression.

CONCLUSIONS

Atomoxetine is efficacious in reducing ADHD symptoms. It may have a role in treating comorbid ODD or depression, and probably in comorbid anxiety.

Seizure risk in patients with attention-deficit-hyperactivity disorder treated with atomoxetine

The comorbidity of seizures, epilepsy, and attention-deficit-hyperactivity disorder (ADHD) prompted the examination of whether atomoxetine use for ADHD is associated with an increased risk of seizures. Seizures and seizure-related symptoms were reviewed from two independent Eli Lilly and Company databases: the atomoxetine clinical trials database and the atomoxetine postmarketing spontaneous adverse event database. Review of clinical trial data indicated that the crude incidence rates of seizure adverse events were between 0.1 and 0.2%, and were not significantly different between atomoxetine, placebo, and methylphenidate. Only 2% of the postmarketing spontaneous reports of seizure events were classified as having no clear contributing or confounding factors, and the reporting rate (8 per 100 000 patients exposed) was within the expected range of population-based incidence. Although children with ADHD are increasingly recognized as being at an elevated risk for seizures, treatment of ADHD symptoms with atomoxetine does not appear to elevate this risk further. The shared vulnerability between ADHD and seizure activity should be taken into account when making treatment decisions for populations of children with epilepsy and children with ADHD.

Atomoxetine versus methylphenidate in paediatric outpatients with attention deficit hyperactivity disorder: a randomized, double-blind comparison trial

OBJECTIVE

To (i) test whether atomoxetine is non-inferior to methylphenidate in treating symptoms of attention deficit hyperactivity disorder (ADHD) in paediatric patients; and (ii) determine the tolerability of the two drugs.

METHOD

This double-blind study was conducted in 6- to 16-year-old outpatients with ADHD (DSM-IV) in China, Korea and Mexico (January-October 2004). Patients were randomly assigned to once-daily atomoxetine (0.8-1.8 mg kg(-1) day(-1); n = 164) or twice-daily methylphenidate (0.2-0.6 mg kg(-1) day(-1); n = 166) for approximately 8 weeks. Primary efficacy assessment was the comparison of response rates (> or =40% reduction from baseline to end point in total score) on the Attention Deficit Hyperactivity Disorder Rating Scale-IV-Parent Version: Investigator-Administered and -Scored. Tolerability measures included, but were not limited to, the assessment of treatment-emergent adverse events (TEAEs) and weight.

RESULTS

Atomoxetine was non-inferior to methylphenidate in improving ADHD symptoms based on response rates (atomoxetine, 77.4%; methylphenidate, 81.5%; one-sided 95% lower confidence limit = -11.7%, p = 0.404). Treatment-emergent adverse effects experienced significantly more frequently in the atomoxetine group, compared with the methylphenidate group, included anorexia (37.2% vs. 25.3%; p = 0.024), nausea (20.1% vs. 10.2%; p = 0.014), somnolence (26.2% vs. 3.6%; p <0.001), dizziness (15.2% vs. 7.2%; p = 0.024) and vomiting (11.6% vs. 3.6%; p = 0.007), most of which were of mild or moderate severity. Atomoxetine-treated patients experienced a small but significantly greater mean weight loss from baseline to end point than methylphenidate-treated patients (-1.2 kg vs. -0.4 kg; p <0.001).

CONCLUSIONS

This study suggests that atomoxetine is non-inferior to methylphenidate in the improvement of ADHD symptoms in paediatric outpatients. Although both of the drugs were well tolerated, atomoxetine was associated with a higher incidence of TEAEs than methylphenidate.

Atomoxetine: a novel treatment for child and adult ADHD

Attention deficit hyperactivity disorder (ADHD) is a common chronic condition with childhood onset that can continue into adulthood. Medication is a fundamental element in the management of this disorder. Atomoxetine is the newest nonstimulant medication approved by the United States Food and Drug Administration (FDA) for the treatment of ADHD. It is the only nonstimulant medication approved by the FDA for treatment of adult ADHD. Atomoxetine is a norepinephrine reuptake inhibitor that selectively inhibits the presynaptic norepinephrine transporter. A growing body of literature supports the use of atomoxetine both in children and adults with ADHD. This paper summarizes information from the literature about atomoxetine, including pharmacokinetics, pharmacodynamics, clinical trials, dosing, and side-effects.

Atomoxetine produces changes in cortico-basal thalamic loop circuits: assessed by phMRI BOLD contrast

Atomoxetine is a selective noradrenaline reuptake inhibitor used in the treatment of attention deficit hyperactivity disorder (ADHD) which has not yet been assessed using pharmacological neuroimaging for its effects on rat brain activity. The pharmacological magnetic resonance imaging (phMRI) blood oxygenation level dependent (BOLD) response was determined in rat brain regions following administration of atomoxetine. Rats were individually placed into a 2.35T Bruker magnet for 60min to achieve basal recording of changes in signal intensity. Either saline (n=9) or atomoxetine hydrochloride (2mg/kg; i.p.; n=10) was then administered and recording continued for a further 90min. Data were analysed for BOLD random effects using statistical parametric maps and time course analysis. The main changes observed were widespread negative BOLD responses in the caudate putamen and changes in brain regions associated with the cortico-basal thalamic loop circuits. BOLD changes in the basal ganglia help explain its efficacy in reducing hyperactivity observed in ADHD patients. Although positive BOLD changes in the prefrontal cortex were limited to the ventral orbital cortex this is an area associated with behavioral control and may be of relevance to the use of the drug in ADHD.

Adult atomoxetine ingestions reported to Texas Poison Control Centers, 2003-2005

BACKGROUND

Limited information exists on outcomes from adult ingestions of atomoxetine reported to poison control centers.

OBJECTIVE

To identify factors that might affect the outcome of adult atomoxetine ingestions reported to poison control centers.

METHODS

Using adult ingestions of atomoxetine alone reported to Texas poison control centers during 2003-2005, the proportion of cases involving serious outcomes was determined for selected variables and evaluated for statistical significance by calculating the rate ratio (RR) and 95% confidence interval (CI).

RESULTS

Of 64 cases identified, 9 (14%) involved serious outcomes. No serious outcomes were reported with a maximum dose of 100 mg or less. Serious outcomes were significantly more likely to occur with a maximum dose of more than 2 capsules (RR 8.25; 95% CI 1.48 to 83.58), where the circumstances of the exposures involved self-harm or malicious intent (RR 6.02; 95% CI 1.30 to 30.35) or when the patient was already at or en route to a healthcare facility when the poison control center was contacted (RR 18.75; 95% CI 2.10 to 886.83) or was referred to a healthcare facility by the poison control center (RR 22.50; 95% CI 1.81 to 1181.19).

CONCLUSIONS

The severity of the outcomes associated with adult atomoxetine ingestions depended on the dose taken and the circumstances of the ingestion. The management of patients with serious outcomes was more likely to involve healthcare facilities. Such information is useful in creating triage guidelines for the management of adult atomoxetine ingestions.

Atomoxetine for hyperactivity in autism spectrum disorders: placebo-controlled crossover pilot trial

OBJECTIVE

To explore placebo-controlled efficacy and safety of atomoxetine (ATX) for attention-deficit/hyperactivity disorder (ADHD) symptoms in children with autism spectrum disorders (ASD).

METHOD

Children ages 5 to 15 with ASD and prominent ADHD symptoms were randomly assigned to order in a crossover of clinically titrated ATX and placebo, 6 weeks each, separated by 1-week washout. Slopes for each condition were compared by paired t test.

RESULTS

In 2004-2005, 12 boys and 4 girls (7 with autistic disorder, 1 Asperger's, 8 pervasive developmental disorder not otherwise specified) all completed at least 3 weeks of each condition. On the primary outcome, the Hyperactivity subscale of the Aberrant Behavior Checklist, ATX was superior to placebo (p =.043, effect size d = 0.90). It was also superior on a 0 to 3 rating of nine DSM-IV ADHD hyperactive/impulsive symptoms (p =.005, d = 1.27), but missed significance on nine inattentive symptoms (p =.053, d= 0.89). Nine subjects responded to ATX, four to placebo (25% improvement on the Hyperactivity subscale plus Clinical Global Impressions-Improvement of 1-2. One was rehospitalized for recurrent violence on ATX. Adverse events were otherwise tolerable, with no tendency to stereotypy.

CONCLUSIONS

ATX appears safe and effective for treating hyperactivity in some children with autism spectrum disorders. The effect appears as large as in a multisite methylphenidate trial in the same population, with fewer intolerable side effects. Further study in autism spectrum disorders is indicated.

Atomoxetine ingestions in children: a report from poison centers

BACKGROUND

Atomoxetine uses a novel non-stimulant approach to the treatment of attention deficit hyperactivity disorder. There is limited information on overdose of atomoxetine in children or adults.

OBJECTIVE

To provide information on atomoxetine in overdose.

METHODS

Case series were conducted at 3 regional poison centers for atomoxetine ingestion in children (age < or = 17 y). Exclusion criteria were polypharmacy or lack of follow-up.

RESULTS

Forty patients were included (25 boys; 63%) in the study. The mean +/- SD age was 6.1 +/- 4.9 years (range 9 mo-17 y). Twenty-five patients were managed at home, 14 in hospital emergency departments (3 children were admitted), and 1 patient was managed in a physician's office. Symptoms reported were tachycardia, drowsiness, nausea, hypertension, and vomiting. A seizure was reported in one child who had recently started atomoxetine therapy. No arrhythmias beyond sinus tachycardia were reported. Mean maximum heart rate in patients with tachycardia was 131 +/- 14 beats/min. The mean dose ingested, categorized by medical outcome, was: no effect (n = 22), 40 +/- 32 mg; minor effect (n = 14), 167 +/- 221 mg; and moderate effect (n = 4), 249 +/- 326 mg. There were no major outcomes or fatalities. The lowest dose ingested that resulted in hypertension was 480 mg, in a 14-year-old girl (BP 136/95 mm Hg).

CONCLUSIONS

In this case series, clinically significant cardiovascular effects requiring direct intervention did not occur. Activated charcoal and/or observation appear to be sufficient for accidental ingestion. Further investigation may be needed to indicate whether seizures occur from atomoxetine ingestion.

Norepinephrine and acetylcholine mediation of the components of reflexive attention: implications for attention deficit disorders

Attention deficit hyperactivity disorders (ADHD) create major learning barriers for children and significant social and legal handicaps for adults worldwide. Important advances in the genetic basis of the disease have been made, but reliable, biological, diagnostic markers remain elusive. This review takes the position that future progress in treating the core symptom of attention deficits requires a clearer understanding of the neuroscience of attention in normal individuals. Two important achievements in this direction have been the development of tasks that identify activity in the orienting, alerting and conflict networks, and the identification of neurotransmitters that mediate these components. The proven ability of these tasks to identify and characterize response components of "normal" attention argues that they could be used advantageously with patient populations. The categorization of neurotransmitter abnormalities in those with ADHD could clarify whether attention deficits occur within or across attention networks. To realize these goals, we evaluate laboratory studies of attention in humans and animals that address the underlying neurotransmitter systems, primarily norepinephrine and acetylcholine. We propose that key facts about deficits in reflexive and voluntary attention may be understood by a model that includes deficits in brain norepinephrine release and its effects on cholinergic activity in the parietal cortex.

A new paradigm for developing drugs in children: atomoxetine as a model

When prescribing drugs for children, it is fundamental to acknowledge that they are distinct from adults with a different physiology and metabolism. They are also still maturing. The development of drugs with a primarily paediatric indication thus requires the trialling of these drugs in a paediatric population to assess safety, tolerability, and efficacy as appropriately as possible. When designing and running a paediatric clinical trial, a number of complexities must be addressed to ensure a successful study, including practical considerations, ethical issues, and tailoring communication appropriately to study participants and parents. The drug development process for atomoxetine, a novel, non-stimulant treatment for attention deficit/hyperactivity disorder (ADHD), encompassed a preclinical programme, initial trials in healthy adults, and a proof of concept trial in adults with ADHD. Open label and placebo controlled studies in paediatric patients followed, thus establishing the drug's safety and efficacy in children with ADHD. Further trials have addressed, and continue to address, wider aspects of the atomoxetine response in a paediatric setting.

Atomoxetine: a new pharmacotherapeutic approach in the management of attention deficit/hyperactivity disorder

Atomoxetine is a novel, non-stimulant, highly selective noradrenaline reuptake inhibitor that has been studied for use in the treatment of attention deficit/hyperactivity disorder (ADHD). Data from clinical trials show it to be well tolerated and effective in the treatment of ADHD in children, adolescents, and adults. Improvements were seen not only in core symptoms of ADHD, but also in broader social and family functioning and self esteem. Once-daily dosing of atomoxetine has been shown to be effective in providing continuous symptom relief. Atomoxetine does not appear to have abuse potential and is associated with a benign side effect profile. The development of atomoxetine thus represents an important advance in the pharmacological management of ADHD.

Non-stimulant medications in the treatment of ADHD

BACKGROUND

Stimulants are the first-line medication in the psychopharmacological treatment of attention-deficit hyperactivity disorder (ADHD). However, 10 to 30% of all children and adults with ADHD either do not respond to or do not tolerate treatment with stimulants.

OBJECTIVE

To describe alternative treatment approaches with various non-stimulant agents, especially atomoxetine.

METHOD

General review of empirically based literature concerning efficacy and safety of the substances.

RESULTS

A large and still increasing body of data supports the usefulness of atomoxetine, a once daily dosing, and new selective noradrenalin reuptake inhibitor, with few side effects. Atomoxetine has been licensed in the US for use in ADHD across the lifespan, and is currently under consideration in Europe. Other non-stimulant substances, such as tricyclic antidepressants (TCAs) and alpha-2-adrenergic agonists, which are used to treat ADHD, are also reviewed. TCAs have been well studied and shown to be efficacious in the treatment of ADHD, but are limited by side effects. The number of studies documenting the efficacy of alpha-2-adrenergic agonists is still limited. Some experimental studies support a potential role of cholinergic drugs such as acetylcholinesterase inhibitors (tacrine, donepezil) as well as novel nicotinic analogues (ABT-418).

CONCLUSION

Non-stimulant agents have been shown to be effective in treatment of ADHD. Especially, atomoxetine seems promising and newline drugs are in development.

Nonstimulant treatment of adult attention-deficit/hyperactivity disorder

A substantial literature supports the viability of nonstimulant treatments for ADHD. Despite their chemical differences, the various compounds with documented anti-ADHD activity share a common noradrenergic/dopaminergic activity. Although TCAs are established alternative treatments forADHD, particularly the more noradrenergic secondary amines (DMI and nortriptyline), their narrow therapeutic index and potential for cardiovascular toxicity have limited their use. The atypical mixed noradrenergic/dopaminergic antidepressant bupropion also has been documented to be effective in treating adults with ADHD in a controlled clinical trial. Recent work with the novel noradrenergic specific agent, atomoxetine, has produced convincing evidence of substantial efficacy, tolerability, and safety in children and adults. Despite these advances, more work is needed to further document the short- and long-term safety and efficacy of stimulants and alternative agents for treating adults with ADHD. It also is hoped that advances in the understanding of the underlying neurobiology of ADHDwill lead to the development of a new generation of safe and effective treatments for this disorder. Such developments have the promise of improving the quality of life of the millions of affected patients and their families worldwide.

Atomoxetine hydrochloride for the treatment of attention-deficit/hyperactivity disorder

BACKGROUND

Attention-deficit/hyperactivity disorder (ADHD) occurs in approximately 3% to 10% of the pediatric population. Most of the drugs typically used to treat ADHD are stimulants, which, because of their addictive properties and potential for abuse, are controlled substances. Although these drugs are the mainstay of treatment for ADHD, nearly one third of patients may not respond to or be able to tolerate them. Atomoxetine hydrochloride, a nonstimulant approved by the US Food and Drug Administration for the treatment of ADHD, may provide an alternative to the use of stimulants.

OBJECTIVE

The goal of this review was to describe the chemistry, mechanism of action, pharmacokinetics, drug interactions, and efficacy and safety profiles of atomoxetine in pediatric and adult patients with ADHD, as well as relevant pharmacoeconomic considerations.

METHODS

Relevant publications were identified through a search of the English-language literature indexed on PreMEDLINE and MEDLINE (1966-May 2003) using the search terms atomoxetine, tomoxetine, and LY139603. These terms were also applied to the Google search engine. All articles were reviewed for suitability for inclusion. The manufacturer of atomoxetine provided both published and unpublished data.

RESULTS

In the data reviewed, atomoxetine was more efficacious than placebo in patients with ADHD (P<0.05 to P<0.01). Therapeutic doses ranged from 45 mg or placebo (P<0.05). These results add support to the hypothesis that atomoxetine may not cause the increase in dopamine concentrations in the nucleus accumbens that is associated with pleasurable effects and abuse potential.

Non-stimulant treatment for Attention-Deficit/Hyperactivity Disorder

A variety of compounds with a common noradrenergic/dopaminergic activity have shown documented anti-Attention-Deficit/Hyperactivity Disorder (ADHD) activity. There is a substantial body of literature documenting the efficacy of tricyclic antidepressants on ADHD in over 1,000 subjects. There is an equally large database on the efficacy of the specific norepinephrlne reuptake inhibitor, atomoxetine, of greater than 2,000 Individuals. In addition, the atypical antidepressant buproplon also has been documented to be effective in the treatment of ADHD in controlled clinical trials. Despite wide use, the scientific base supporting the efficacy of alpha-2, noradrenergic agonists is somewhat limited. Several lines of evidence provide preliminary support for the potential benefits of cholinergic cognitive enhandng drugs, such as anticholinesterase inhibitors (tacrine, donepezil) as well as novel nicotinic analogues (ABT-418). Despite these promising results, more research is needed on alternative pharmacological treatments for the treatment of ADHD.

A transgenic model of comorbid Tourette's syndrome and obsessive-compulsive disorder circuitry

The tic disorder Tourette's Syndrome (TS) and obsessive-compulsive disorder (OCD) are comorbid behavioral disorders, suggesting a shared but still unknown neuronal basis. To 'circuit-test' such behaviors, we previously engineered transgenic mice expressing a neuropotentiating protein (cholera toxin A1 subunit) within a cortical-limbic subset of dopamine D1-receptor expressing (D1+) neurons known to trigger glutamatergic excitation of orbitofrontal, sensorimotor, limbic and efferent striatal circuits thought to be hyperactive or affected in OCD and TS. These mice exhibited OCD-like behaviors including generalized behavioral perseveration and compulsion-like leaping and grooming-associated pulling and biting of skin and hair. We now report that these OCD-like mice, like humans, also exhibit comorbid TS-like behaviors, including juvenile-onset tics; increased tic number, complexity and flurries; increased tic severity in males; voluntary tic suppression; and tic responsiveness to a non-cataleptic TS+OCD drug therapy (clonidine, 0.01 mg kg(-1)). These data suggest that hormonal gender differences, apart from the influence of genetic or autoimmune etiologic factors, may be sufficient to aggravate tic severity in human TS males compared to TS females. These data also proffer a precise neuronal basis for TS+OCD, wherein tics and primary compulsions or obsessions are evoked by hyperactivity of various cortical-limbic projection neurons' glutamatergic output to efferent targets like the striatum. The 'Cortical-limbic Glutamatergic Neuron' (CGN) neuronal circuit model merges formerly opposed neurotransmitter models of TS and OCD, and is consistent with new clinical reports of increased cortical hyperactivity, striatal glutamate and striatal inhibitory D2 receptors, and reduced striatal responsiveness, in these disorders.