Pharmacological Alternatives to Psychostimulants for the Treatment of Attention-Deficit/Hyperactivity Disorder

Pharmacotherapy of Traumatic Childhood Aphasia: Beneficial Effects of Donepezil Alone and Combined With Intensive Naming Therapy

At present, language therapy is the only available treatment for childhood aphasia (CA). Studying new interventions to augment and hasten the benefits provided by language therapy in children is strongly needed. CA frequently emerges as a consequence of traumatic brain injury and, as in the case of adults, it may be associated with dysfunctional activity of neurotransmitter systems. The use of cognitive-enhancing drugs, alone or combined with aphasia therapy, promotes improvement of language deficits in aphasic adults. In this study we report the case of a 9-year-old right-handed girl, subject P, who had chronic anomic aphasia associated with traumatic lesions in the left temporal-parietal cortex. We performed a single-subject, open-label study encompassing administration of the cholinergic agent donepezil (DP) alone during 12 weeks, followed by a combination of DP and intensive naming therapy (INT) for 2 weeks and thereafter by a continued treatment of DP alone during 12 weeks, a 4-week washout period, and another 2 weeks of INT. Four comprehensive language and neuropsychological evaluations were performed at different timepoints along the study, and multiple naming evaluations were performed after each INT in order to assess performance in treated and untreated words. Structural magnetic resonance imaging (MRI) was performed at baseline. MRI revealed two focal lesions in the left hemisphere, one large involving the posterior inferior and middle temporal gyri and another comprising the angular gyrus. Overall, baseline evaluation disclosed marked impairment in naming with mild-to-moderate compromise of spontaneous speech, repetition, and auditory comprehension. Executive and attention functions were also affected, but memory, visuoconstructive, and visuoperceptive functions were preserved. Treatment with DP alone significantly improved spontaneous speech, auditory comprehension, repetition, and picture naming, in addition to processing speed, selective, and sustained attention. Combined DP-INT further improved naming. After washout of both interventions, most of these beneficial changes remained. Importantly, DP produced no side effects and subject P attained the necessary level of language competence to return to regular schooling. In conclusion, the use of DP alone and in combination with INT improved language function and related cognitive posttraumatic deficits in a child with acquired aphasia. Further studies in larger samples are warranted.

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.

Treatment of attention deficit hyperactivity disorder in adults

A number of medication and psychologic treatment options for adults with attention deficit hyperactivity disorder have become available during the past 5 years, while others are under investigation. This review describes the safety and effectiveness of the stimulants (i.e., methylphenidate and dexedrine), and particularly the newer long-acting stimulants (i.e., Concerta) and Adderall XR) in the treatment of this population. Some nonstimulant/nonantidepressants, particularly atomoxetine, have also been shown to improve attention deficit hyperactivity disorder symptoms. Combination treatment of stimulants and antidepressants require more study with regard to safety and efficacy. Psychosocial interventions (e.g., cognitive behavioral therapy, mindfulness training and cognitive remediation) can also benefit adults with attention deficit hyperactivity disorder. Cognitive behavioral therapy combined with medication is more effective than either intervention alone, especially for addressing the emotional and functional aspects of peoples lives and thus improving occupational, interpersonal and emotional outcomes.

A high density linkage disequilibrium mapping in 14 noradrenergic genes: evidence of association between SLC6A2, ADRA1B and ADHD

Pharmacological evidence suggests the importance of noradrenergic and other monoaminergic neurotransmitters in the aetiology and treatment of attention deficit hyperactivity disorder (ADHD). Until recently, the genes of the noradrenergic pathway were not intensively investigated in ADHD compared to dopaminergic and serotonergic candidates. In this study, 91 SNP markers of 14 noradrenergic genes (an average density of one SNP per 4.5 kbp) were examined in ADHD samples from Ireland and Australia. Although suggestive evidence of association (nominal p ≤ 0.05) with the genes SLC6A2, ADRA1A, ADRA1B and ADRA2B was observed, none remained significant after permutation adjustments. In contrast, haplotype analyses demonstrated a significant association between ADHD and a SLC6A2 haplotype comprising the markers rs36009, rs1800887, rs8049681, rs2242447 and rs9930182 (χ(2) = 9.39, p-corrected = 0.019, OR = 1.51). A rare ADRA1B haplotype made of six SNPs (rs2030373, rs6884105, rs756275, rs6892282, rs6888306 and rs13162302) was also associated (χ(2) = 7.79, p-corrected = 0.042 OR = 2.74) with the disorder. These findings provide evidence of a contribution of the noradrenaline system to the genetic aetiology of ADHD. The observed haplotype association signals may be driven by as yet unidentified functional risk variants in or around the associated regions. Functional genomic analysis is warranted to determine the biological mechanism of the observed association.

Effects of serotonin-norepinephrine reuptake inhibitors on locomotion and prefrontal monoamine release in spontaneously hypertensive rats

Catecholamine neurotransmission in the prefrontal cortex plays a key role in the therapeutic actions of drugs for attention-deficit/hyperactivity disorder (ADHD). Recent clinical studies show that several serotonin-norepinephrine reuptake inhibitors have potential for treating ADHD. In this study, we examined the effects of acute treatment with serotonin-norepinephrine reuptake inhibitors on locomotion and the extracellular levels of monoamines in the prefrontal cortex in spontaneously hypertensive rats (SHR), an animal model of ADHD. Adolescent male SHR exhibited greater horizontal locomotion in an open-field test than male WKY control rats. Psychostimulant methylphenidate (0.3 and 1 mg/kg), the selective norepinephrine reuptake inhibitor atomoxetine (1 and 3 mg/kg), and serotonin-norepinephrine reuptake inhibitors duloxetine (10 mg/kg), venlafaxine (10 and 30 mg/kg) and milnacipran (30 mg/kg) reduced the horizontal activity in SHR, but did not affect in WKY rats. The selective norepinephrine reuptake inhibitor reboxetine (10 mg/kg) and the tricyclic antidepressant desipramine (10 and 30 mg/kg) also reduced the horizontal activity in SHR, whereas the selective serotonin reuptake inhibitor citalopram (30 mg/kg) did not. Microdialysis studies showed that atomoxetine, methylphenidate, duloxetine, venlafaxine, milnacipran, and reboxetine increased the extracellular levels of norepinephrine and dopamine in the prefrontal cortex in SHR. Citalopram did not affect norepinephrine and dopamine levels in the prefrontal cortex, although it increased the serotonin levels. Neither duloxetine nor venlafaxine increased the dopamine levels in the striatum. These findings suggest that serotonin-norepinephrine reuptake inhibitors, similar to methylphenidate and atomoxetine, have potential for ameliorating motor abnormality in the SHR model.

Pharmacokinetics and pharmacodynamics of edivoxetine (LY2216684), a norepinephrine reuptake inhibitor, in pediatric patients with attention-deficit/hyperactivity disorder

OBJECTIVE

Edivoxetine (LY2216684) is a selective and potent norepinephrine reuptake inhibitor (NERI). The pharmacokinetics (PK) and pharmacodynamics (PD) of edivoxetine were assessed in children and adolescent patients with attention-deficit/hyperactivity disorder (ADHD) following single and once-daily oral doses of edivoxetine.

METHODS

During a phase 1 open-label safety, tolerability, and PK study, pediatric patients were administered edivoxetine at target doses of 0.05, 0.1, 0.2 and 0.3 mg/kg, and blood samples were collected to determine plasma concentrations of edivoxetine for PK assessments and plasma 3,4-dihydroxyphenylglycol (DHPG) concentrations for PD assessments. Edivoxetine plasma concentrations were measured using liquid chromatography with tandem mass spectrometric detection, and DHPG was measured using liquid chromatography with electrochemical detection.

RESULTS

Edivoxetine PK was comparable between children and adolescents. The time to maximum concentration (t(max)) of edivoxetine was ∼2 hours, which was followed by a mono-exponential decline in plasma concentrations with a terminal elimination half-life (t(1/2)) of ∼6 hours. Dose-dependent increases in area under the edivoxetine plasma concentration versus time curve from zero to infinity (AUC(0-∞)) and maximum plasma concentration (C(max)) were observed, and there was no discernable difference in the apparent clearance (CL/F) or the apparent volume of distribution at steady state (V(ss)/F) across the dose range. In adolescents, edivoxetine caused a maximum decrease in plasma DHPG concentrations from baseline of ∼28%, most notably within 8 hours of edivoxetine administration.

CONCLUSION

This initial study in pediatric patients with ADHD provides new information on the PK profile of edivoxetine, and exposures that decrease plasma DHPG consistent with the mechanism of action of a NERI. The PK and PD data inform edivoxetine pharmacology and can be used to develop comprehensive population PK and/or PK-PD models to guide dosing strategies.

Methylphenidate enhances inhibitory synaptic transmission by increasing the content of norepinephrine in the locus coeruleus of juvenile rats

The present study examined the effect of methylphenidate (MPH), a psychostimulant, on nor-adrenergic transmission in the locus coeruleus (LC) of juvenile rats. Intracellular recordings showed that MPH (>3 µM) produced a hyperpolarizing response associated with a decrease in the rate of spontaneously firing action potentials. MPH (1 µM) enhanced the amplitude of the inhibitory postsynaptic potential (IPSP) mediated by norepinephrine (NE), but did not change the excitatory postsynaptic potential (EPSP) mediated by excitatory amino acids. Whole-cell patch-clamp recordings showed that MPH (0.3-30 µM) produced an outward current (I(MPH)) and enhanced the inhibitory postsynaptic current (IPSC) in neurons of the juvenile rat LC. MPH (30 µM) enhanced the NE-induced outward current (I(NE)). Bath-application of yohimbine (1 µM) produced an inward current and blocked the MPH-induced enhancement of the IPSC. Yohimbine (1 µM) depressed not only the I(NE) but also the I(MPH) in juvenile rat LC neurons. The current-voltage relationship of the I(MPH) showed inward rectification and reversed polarity at -91.1±4.3 mV (n=5). Ba(2+) (100 µM) blocked the I(MPH), indicating that the I(MPH) is mediated by Ba(2+)-sensitive inward rectifier K(+) current. These results suggest that MPH enhances inhibitory synaptic transmission by increasing the concentration of NE at noradrenergic synapses in juvenile rat LC neurons.

Atomoxetine and methylphenidate treatment in children with ADHD: the efficacy, tolerability and effects on executive functions

The aim of this study was to compare the safety, efficacy, tolerability, and the effects of atomoxetine and OROS-MPH on executive functions in children with ADHD. This study was an open-label study that only included two medication groups. Children were randomized to open-label atomoxetine or OROS-MPH for 12 weeks. Primary efficacy measures were T-DSM-IV-S, CGI-I and neuropsychological tests battery. Safety assessments included electrocardiogram, adverse events checklist and laboratory tests. According to the endpoint improvement scores of CGI and parents T-DSM-IV-S, treatment responses were not significantly different between the two study groups. OROS-MPH led to a significantly greater reduction in teacher T-DSM-IV-S scale scores. OROS-MPH was more effective than atomoxetine on Stroop-5 time and number of corrections. Significant decrease in the percentage of perseverative errors on WCST in the OROS-MPH group was seen (p = 0.005). The most frequently reported adverse events in the atomoxetine group were anorexia, nausea, nervousness, weight loss, abdominal pain, and somnolence. In the OROS-MPH group, patients most frequently reported anorexia, nervousness, insomnia, headache, nausea, and weight loss. When all these results are considered, although both drugs can be considered effective in ADHD treatment, more remarkable improvement is provided by OROS-MPH based on the rates across informant (i.e., teachers, clinicians) and neuropsychological evaluation.

The neuropharmacology of ADHD drugs in vivo: insights on efficacy and safety

Results from in vivo techniques, especially intracerebral microdialysis in freely-moving rats, have provided insights into potential mechanisms responsible for the efficacy and safety of catecholaminergic drugs for ADHD treatment. The drugs reviewed come from distinct pharmacological classes: psychostimulant releasing agents, eg d-amphetamine; psychostimulant reuptake inhibitors, eg dl-threo-methylphenidate (dl-MPH), and non-stimulant reuptake inhibitors, eg atomoxetine. Psychostimulants, which currently deliver the best efficacy in treating ADHD, exhibit the following characteristics on extraneuronal catecholamine concentrations in rodent brain in vivo: 1) They enhance the efflux and function of both noradrenaline and dopamine in the central nervous system. 2) The increase of dopamine efflux that they produce is not limited to cortical regions. 3) They have a rapid onset of action with no ceiling on drug effect. d-Amphetamine has a mechanism independent of neuronal firing rate, displacing intraneuronal stores of catecholamines, delaying their reuptake and inhibiting catabolism by monoamine oxidase. dl-MPH has an enigmatic, extraneuronal action that is neuronal firing rate-dependent and reuptake transporter-mediated, yet paradoxically, almost as powerful as that of d-amphetamine. In safety terms, these powerful catecholaminergic effects also make the psychostimulants liable for abuse. Since efficacy and safety derive from the same pharmacological mechanisms, it has not yet been possible to separate these two components. However, the development of once-daily psychostimulant formulations and a prodrug, lisdexamfetamine, has improved patient compliance and markedly reduced scope for their diversion/abuse. This review will discuss the in vivo pharmacological profiles of approved catecholaminergic drugs for treatment of ADHD and implications for their clinical efficacy and abuse liability.

Antidepressants in the treatment of adult attention-deficit hyperactivity disorder: a systematic review

INTRODUCTION

Stimulant medications are the most effective drugs in the treatment of attention-deficit hyperactivity disorder (ADHD) in children and in adults. However, some patients do not respond to this treatment and other patients suffer from adverse effects. Very often there are also comorbid disorders that warrant treatment or there is somatic comorbidity that precludes the prescription of stimulants. As a result, alternative treatments for the treatment of ADHD have been explored, such as antidepressant agents. In this systematic review the evidence base for the effect of antidepressants for ADHD in adult patients is determined.

METHODS

Electronic and hand searches were conducted in order to identify clinical trials studying antidepressants for the treatment of ADHD in adult patients. The trials were screened for methodological characteristics and treatment-effect sizes. The odds ratio was calculated for randomized controlled trials with bupropion. A descriptive review of all the randomized controlled studies and an overview of the nonrandomized studies was developed.

RESULTS

Only eight randomized controlled trials were retrieved with four different compounds. Five studies concerned bupropion and the meta-analysis indicates a beneficial effect for bupropion compared with placebo as measured with the Clinical Global Improvement Scale (odds ratio 2.42 [95% CI 1.09 to 5.36]). Several studies suffer from clinical and methodological shortcomings, such as exclusion of patients with comorbid disorders, short treatment duration, or a lack of information with respect to the randomization procedure.

CONCLUSION

Although there is a need for alternative interventions for the treatment of ADHD, such as with antidepressant agents, the evidence base is not large. Only treatment with bupropion seems to have a medium-range effect size, but this is less than that of stimulant medications.

[Alternative agents used in ADHD]

Attention-deficit/hyperactivity disorder (ADHD) is, with a prevalence of 2% to 6%, one of the most common neurobehavioral disorder affecting children and adolescents, persisting into adulthood. Comorbidity and psychosocial circumstances enter into the choice of intervention strategies. Several agents have been demonstrated effective in treating individuals with ADHD. Direct or indirect attenuation of dopamine and norepinephrine neurotransmission appears closely related to both the stimulant and nonstimulant medications efficacious in ADHD. However, important differences concerning efficacy and side effects exist both between and with the specific classes of agents like neuroleptics, antidepressants, antiepileptics, alpha-agonists, beta-blockers, buspiron, l-dopa, melatonin, pycnogenol, zinc, magnesium, polyunsaturated fatty acids, and homeopathy. Elucidating the various mechanisms of action of ADHD medications may lead to better choices in matching potential responses to the characteristics of individuals. We review the purported mechanism of action and available evidence for selected complementary and alternative medicine therapies for ADHD in childhood and adolescence.

Pharmacological models of ADHD

For more than 50 years, heavy metal exposure during pre- or post-natal ontogeny has been known to produce long-lived hyperactivity in rodents. Global brain injury produced by neonatal hypoxia also produced hyperactivity, as did (mainly) hippocampal injury produced by ontogenetic exposure to X-rays, and (mainly) cerebellar injury produced by the ontogenetic treatments with the antimitotic agent methylazoxymethanol or with polychlorinated biphenyls (PCBs). More recently, ontogenetic exposure to nicotine has been implicated in childhood hyperactivity. Because attention deficits most often accompany the hyperactivity, all of the above treatments have been used as models of attention deficit hyperactivity disorder (ADHD). However, the causation of childhood hyperactivity remains unknown. Neonatal 6-OHDA-induced dopaminergic denervation of rodent forebrain also produces hyperactivity - and this model, or variations of it, remain the most widely-used animal model of ADHD. In all models, amphetamine (AMPH) and methylphenidate (MPH), standard treatments of childhood ADHD, typically attenuate the hyperactivity and/or attention deficit. On the basis of genetic models and the noted animal models, monoaminergic phenotypes appear to most-closely attend the behavioral dysfunctions, notably dopaminergic, noradrenergic and serotoninergic systems in forebrain (basal ganglia, nucleus accumbens, prefrontal cortex). This paper describes the various pharmacological models of ADHD and attempts to ascribe a neuronal phenotype with specific brain regions that may be associated with ADHD.

Fatigue, depression, and insomnia: evidence for a symptom cluster in cancer

OBJECTIVES

To review the evidence for considering fatigue, depression, and insomnia as a symptom cluster in cancer.

DATA SOURCES

Empirical studies, clinical articles, and review articles.

CONCLUSION

The single- and multi-symptom measurement approaches are of limited usefulness in distinguishing fatigue, depression, and insomnia. Studies in which these symptoms have been measured concurrently in patients with cancer yield consistent evidence of high positive correlations. Results do not appear to be solely a function of overlap in measurement approaches.

IMPLICATIONS FOR NURSING PRACTICE

Successful management of fatigue, depression, and insomnia in cancer patients are likely to combine pharmacologic and nonpharmacologic therapies.

Effects of long-term atomoxetine treatment for young children with attention-deficit/hyperactivity disorder

OBJECTIVE

The purpose of this 13-study (seven double-blind/placebo-controlled, six open-label) meta-analysis is to determine the effectiveness and tolerability of long-term atomoxetine treatment among young children with attention-deficit/hyperactivity disorder (ADHD).

METHOD

Data were pooled from 6- and 7-year-olds (N = 272) who met DSM-IV criteria for ADHD, received atomoxetine treatment, and were enrolled in clinical trials of > or =2 years. Of these, 97 subjects reached the 24-month time point, providing data for long-term trend analysis of safety and effectiveness.

RESULTS

Effectiveness for most subjects was maintained over long-term treatment, as demonstrated by total scores and total T scores on the Attention-Deficit/Hyperactivity Disorder Rating Scale-IV-Parent Version, investigator administered and scored. During the 2-year period, 25.7% discontinued because of lack of effectiveness, but adverse events were clinically minor and transient, and only 4.0% of children discontinued because of an adverse event. Notable effects on growth were seen during early phases of the study, with attenuation occurring by the 2-year time point. Statistically significant increases in pulse and blood pressure and decreases in cardiac PR interval were seen, but no changes were deemed both statistically significant and clinically meaningful among any vital signs, electrocardiographic measures, or laboratory tests.

CONCLUSION

Long-term atomoxetine treatment appears generally well tolerated and effective in the treatment of young children with ADHD.

Decreased use of clonidine following treatment with atomoxetine in children with ADHD

The objectives of the present study were to examine clonidine use before and after initiation of atomoxetine in a cohort of children with attention deficit/hyperactivity disorder (ADHD). For this purpose, medical and pharmaceutical claims data for patients from 75 managed health care plans across the United States were extracted to identify a cohort of patients aged 18 years and younger at the time of a first atomoxetine prescription. Clonidine users were characterized on the basis of demographics, comorbid conditions, medication use and provider types, and prescribing patterns before and after the index atomoxetine prescription assessed. Subgroups of patients switching from clonidine to atomoxetine were examined and predictors of ongoing or new clonidine use were assessed. Of patients filling a first prescription for atomoxetine, 9.6% received a prescription for clonidine at some time and 4.3% within the previous 2 months. Children identified with a hyperactive component to their ADHD, those with more complex diagnostic histories, and those with tics and sleep disorders were particularly likely to receive clonidine. More than a third of patients (36.5%) with recent clonidine use subsequently discontinued use, with the pattern of clonidine use before and after atomoxetine use being highly dependent upon the pattern of stimulant prescription. Atomoxetine, in some cases, seems to have replaced clonidine in the treatment of patients with ADHD complicated with comorbid psychiatric disorders. In others, atomoxetine has replaced both stimulant and clonidine in patients previously requiring this combination for the control of symptoms or for the management of stimulant-related adverse effects.

Atomoxetine versus stimulants for treatment of attention deficit/hyperactivity disorder

OBJECTIVE

To identify, review, and analyze studies comparing atomoxetine with psychostimulants with the intent of determining the role of atomoxetine in the pharmacologic management of attention deficit/hyperactivity disorder (ADHD).

DATA SOURCES

Primary, review, and meta-analysis articles were identified by a MEDLINE search (1966-December 2005). MeSH headings used in the search include: attention deficit/hyperactivity disorder, ADHD, atomoxetine, stimulants, psychostimulants, methylphenidate, and amphetamine salts. Relevant data presented at professional meetings that we attended were also identified.

STUDY SELECTION AND EXTRACTION

All clinical studies comparing atomoxetine with psychostimulants, regardless of study design, were evaluated. Relevant efficacy and safety data from these studies were included in the discussion.

DATA SYNTHESIS

At time of writing, 5 head-to-head trials had compared psychostimulants and atomoxetine in the treatment of ADHD. No significant difference between atomoxetine and methylphenidate immediate-release were found on the ADHD Rating Scale total score. Osmotic oral release system (OROS) methylphenidate showed significantly greater improvement at weeks 1 and 2, and significantly more patients treated with OROS methylphenidate were classified as responders. Patients on both atomoxetine and mixed amphetamine salts extended-release (MAS XR) showed significant improvements at endpoint over baseline; however, Swanson, Kotkin, Agler, M-Flynn, and Pelham (SKAMP) scores were significantly better with MAS XR. Tolerability was similar between atomoxetine and stimulant medications.

CONCLUSIONS

Based on available evidence, psychostimulants are regarded as first-line pharmacologic treatment for children and adolescents with ADHD, as the efficacy and safety of these agents have been well established based on clinical trials and extensive naturalistic use. Adverse effects in some patients and abuse potential have led to the search for new treatments. Atomoxetine represents an alternative treatment for ADHD and is unlikely to be associated with abuse; however, long-term safety data are needed to further establish its place in therapy.

1-(4-Methylphenyl)-2-pyrrolidin-1-yl-pentan-1-one (Pyrovalerone) analogues: a promising class of monoamine uptake inhibitors

Dopamine, serotonin, and norepinephrine are essential for neurotransmission in the mammalian system. These three neurotransmitters have been the focus of considerable research because the modulation of their production and their interaction at monoamine receptors has profound effects upon a multitude of pharmacological outcomes. Our interest has focused on neurotransmitter reuptake mechanisms in a search for medications for cocaine abuse. Herein we describe the synthesis and biological evaluation of an array of 2-aminopentanophenones. This array has yielded selective inhibitors of the dopamine and norepinephrine transporters with little effect upon serotonin trafficking. A subset of compounds had no significant affinity at 5HT1A, 5HT1B, 5HT1C, D1, D2, or D3 receptors. The lead compound, racemic 1-(4-methylphenyl)-2-pyrrolidin-1-yl-pentan-1-one 4a, was resolved into its enantiomers and the S isomer was found to be the most biologically active enantiomer. Among the most potent of these DAT/NET selective compounds are the 1-(3,4-dichlorophenyl)- (4u) and the 1-naphthyl- (4t) 2-pyrrolidin-1-yl-pentan-1-one analogues.

Desipramine attenuates working memory impairments induced by partial loss of catecholamines in the rat medial prefrontal cortex

RATIONALE

The density of tyrosine hydroxylase-immunoreactive (TH-IR) axons in the prefrontal cortex of schizophrenic subjects may be reduced by as much as 50% in the deep cortical layers (Am J Psychiatry 156:1580-1589, 1999). Previously, we demonstrated that approximately 60% loss of TH-IR axons in the rat medial prefrontal cortex (mPFC) decreases local basal and stress-evoked extracellular dopamine (DA) concentrations, suggesting that moderate loss of DA axons in the mPFC is sufficient to alter the neurochemical activity of the remaining DA neurons (Neuroscience 93:497-505, 1999).

OBJECTIVES

To further assess the functional consequences of partial mPFC DA depletion, we examined the effects of 6-hydroxydopamine lesions of the rat mPFC on behavior in a T-maze delayed-response task. We also assessed whether chronic administration of the norepinephrine (NE) uptake inhibitor, desipramine (DMI), attenuates lesion-induced deficits in T-maze performance. Previous research indicates that inhibition of NE transport in the mPFC results in a concomitant increase in extracellular DA and NE.

RESULTS

Moderate loss of mPFC DA and NE (approximately 50 and 10% loss, respectively) was sufficient to impair delayed-response behavior, in part due to an increase in perseverative responding. Chronic DMI treatment (3 mg/kg delivered via osmotic pumps) impaired performance of control rats but attenuated the deficits in delayed-response behavior in rats previously sustaining loss of mPFC DA and NE (approximately 75 and 35% loss, respectively).

CONCLUSION

These data suggest that moderate loss of DA and NE in the prefrontal cortex is sufficient to impair cognitive function, and these behavioral effects are attenuated by inhibition of the NE transporter.

Mechanisms differentiating normal from abnormal aggression: glucocorticoids and serotonin

Psychopathology-associated human aggression types are induced by a variety of conditions, are behaviorally variable, and show a differential pharmacological responsiveness. Thus, there are several types of abnormal human aggression. This diversity was not reflected by conventional laboratory approaches that focused on the quantitative aspects of aggressive behavior. Recently, several laboratory models of abnormal aggression were proposed, which mainly model hyperarousal-driven aggressiveness (characteristic to intermittent explosive disorder, post-traumatic stress disorder, depression, chronic burnout, etc.) and hypoarousal-driven aggressiveness (characteristic mainly to antisocial personality disorder and its childhood antecedent conduct disorder). Findings obtained with these models suggest that hyperarousal-driven aggressiveness has at its roots an excessive acute glucocorticoid stress response (and probably an exaggerated response of other stress-related systems), whereas chronic hypoarousal-associated aggressiveness is due to glucocorticoid deficits that affect brain function on the long term. In hypoarousal-driven aggressiveness, serotonergic neurotransmission appears to lose its impact on aggression (which it has in normal aggression), certain prefrontal neurons are weakly activated, whereas the central amygdala (no, or weakly involved in the control of normal aggression) acquires important roles. We suggest that the specific study of abnormal aspects of aggressive behavior would lead to important developments in understanding the specific mechanisms underlying different forms of aggression, and may ultimately lead to the development of better treatment approaches.

Attention deficit hyperactivity disorder and borderline personality disorder

To evaluate the association between attention deficit hyperactivity disorder (ADHD) and the diagnosis of borderline personality disorder (BPD) in adulthood, a systematic review of published follow-up data, mainly from observational studies was done. Electronic databases Medline, PsychInfo and PSYNDEXplus were searched from their earliest entries. All studies suggested significant relationships between ADHD and BPD. From a phenomenological point of view there seem to exist some similarities between these two disorders: deficits in affect regulation and impulse control, substance abuse, low self esteem and disturbed interpersonal relationship are common in both conditions. From a neuropsychological point of view dissociation in BPD might be regarded as a special form of behavioral inhibition and sustained attention comparable to ADHD. Possible therapeutic strategies of comorbid ADHD and BPD are discussed.

Reboxetine as an optional treatment for hyperkinetic conduct disorder: a prospective open-label trial

BACKGROUND AND PURPOSE

Hyperkinetic conduct disorder (HCD) has been identified as a common psychiatric diagnosis among children and adolescents. This disorder affects many life aspects of both child and family. The aim of this study was to examine the efficacy of the selective norepinephrine reuptake inhibitor (SNRI), reboxetine, in treating children with HCD and its influence on associated symptoms, such as aggressiveness, impulsivity, anxiety, and depression.

METHODS

Fifteen children, 5-14 years of age, diagnosed with HCD, participated in a 12- week, prospective, open-label trial with reboxetine (4-8 mg/d). They were examined for changes in: ADHD symptoms, as measured by the Conners Abbreviated (10-item) Teacher Rating Scale, aggression, as measured by the Yudofsky Overt Aggression Scale (OAS), impulsivity, as measured by the Plutchik impulsivity scale (IS), anxiety, as measured by the Revised Children's Manifest Anxiety Scale (RCMAS), and depressive mood, as measured by the Hamilton Rating Scale for Depression (HAM-D).

RESULTS

There was a significant symptomatic improvement for HCD symptoms and associated symptoms.

CONCLUSION

Our findings suggest that reboxetine may be effective in the treatment of HCD and associated symptoms.

The relationship of cancer symptom clusters to depressive affect in the initial phase of palliative radiation

Research on comorbidity across cancer symptoms, including pain, fatigue, and depression, could suggest if crossover effects from symptom-specific interventions are plausible. Secondary analyses were conducted on a survey of 268 cancer patients with recurrent disease from a northeastern U.S. city who were initiating palliative radiation for bone pain. Moderator regression analyses predicted variation in depressive affect that could be attributed to symptom clusters. Patients self-reported difficulty controlling each physical symptom over the past month on a Likert scale and depressive symptoms on a validated depression measure (Center for Epidemiologic Studies-Depression [CES-D]) over the past week on a four-category scale. An index of depressive affect was based on items of negative and positive affect from the CES-D. In predicting depressive affect, synergistic interactions of pain with fever, fatigue, and weight loss suggest separate pathways involving pain. A similar interaction with fever occurs when nausea was tested in place of pain. Further, the interaction between pain and fatigue is similar in form to the interaction between difficulty breathing and fatigue (when sleep is not a problem). Follow-up to the latter interaction reveals: 1) additional moderation by hypertension and palliative radiation to the hip/pelvis; and 2) a similar cluster not involving hypertension when appetite problems and weight loss were tested in place of fatigue. The significance and form of these interactions are remarkably consistent. Similar sickness mechanisms could be generating: 1) pain and nausea during fever; 2) pain and fatigue during weight loss; and 3) pain and breathing difficulty when fatigue is pronounced. Crossover effects from symptom-specific interventions appear promising.

Self-regulation and inhibition in comorbid ADHD children: an evaluation of executive functions

The relationship between executive function and comorbid diagnoses in ADHD children is examined. One hundred six children between 7 and 15 years of age are assessed using the Tower of London (TOL), a test of executive function, and the Kiddie Schedule of Affective Disorders and Schizophrenia, Present and Lifetime Version, a diagnostic interview. All children met the diagnostic criteria for ADHD. A majority of the children had comorbid anxiety disorders, mood disorders, or oppositional defiant disorder. Measures on the TOL are total move score, total initiation time, and total rule violations. Age is predictive in all three measures of executive function as assessed by the TOL. Gender is predictive of total initiation time and total rule violations. Comorbid disorders are found to not have significance on executive function as measured by the TOL. This study concludes that comorbid disorders may not affect executive function.

Efficacy and safety of atomoxetine in childhood attention-deficit/hyperactivity disorder with comorbid oppositional defiant disorder

OBJECTIVE

To compare the safety and efficacy of atomoxetine, a selective inhibitor of the norepinephrine transporter, versus placebo in Attention-Deficit/Hyperactivity Disorder (ADHD) patients with comorbid Oppositional Defiant Disorder (ODD).

METHODS

A subset analysis of 98 children from two identical, multi-site, double-blind, randomized, placebo-controlled trials involving 9 weeks of treatment with atomoxetine or placebo was conducted. Patients met DSM-IV ADHD criteria. ODD was diagnosed with the Diagnostic Interview for Children and Adolescents-IV (DICA-IV; Reich, Weiner, and Herjanic, 1997). ADHD severity was assessed with the ADHD Rating Scale-IV-Parent Version: Investigator Administered and Scored (ADHD-RS-IV-Parent:lnv; DuPaul, Power, Anastopoulos, and Reid, 1998); the short version of the Conners' Parent Rating Scales-Revised (CPRS-R:S; Conners, 2000); and the Clinical Global Impressions of ADHD Severity (CGI-ADHD-S; Guy, 1976). Clinical response was defined as a > or = 25% reduction in ADHD-RS-IV-Parent:lnv total score.

RESULTS

ADHD-RS-IV-Parent:lnv, CGI-ADHD-S, and three CPRS-R:S subscale scores improved markedly with atomoxetine treatment. However, a decrease in the CPRS-R:S Oppositional subscore for atomoxetine-treated patients was not significantly greater than scores for placebo-treated patients. Clinical response rates were 65.4% in the atomoxetine group, and 36.4% in the placebo group (p = .007).

CONCLUSION

Atomoxetine was effective for the treatment of ADHD in patients with comorbid ODD. It did not significantly reduce the severity of ODD symptoms, and was well tolerated by the patients.

Bupropion sustained release treatment reduces fatigue in cancer patients

OBJECTIVE

To demonstrate that bupropion sustained release (SR) can reduce the symptoms of fatigue experienced by cancer patients.

METHOD

We studied an open-label case series of outpatients with fatigue referred for psychiatric assessment from a tertiary care cancer centre. Inclusion criteria were the presence of fatigue or depression with marked fatigue. Clinical status was assessed using the Global Clinical Improvement scale.

RESULTS

Fifteen subjects with various cancer sites and psychiatric diagnoses were treated with bupropion SR (modal dose 150 mg) for up to 2 years. Most (13 of 15) saw improvement. Thirteen patients had minor, expectable side effects, and 10 patients were able to continue with bupropion for an extended time. All subjects who improved showed improvement within 2 to 4 weeks.

CONCLUSIONS

This is the first report that shows bupropion SR can reduce fatigue in cancer patients. Controlled studies with more homogeneous samples would be necessary to establish the efficacy of this intervention. Further studies should address whether this effect of bupropion is separate from its action as an antidepressant.

Dopamine hypofunction possibly results from a defect in glutamate-stimulated release of dopamine in the nucleus accumbens shell of a rat model for attention deficit hyperactivity disorder--the spontaneously hypertensive rat

RUSSELL, V.A. Dopamine hypofunction possibly results from a defect in glutamate-stimulated release of dopamine in the nucleus accumbens shell of a rat model for attention deficit hyperactivity disorder-the spontaneously hypertensive rat. NEUROSCI. BIOBEHAV. REV.27(2003). Disturbances in glutamate, dopamine and norepinephrine function in the brain of a genetic animal model for attention-deficit hyperactivity disorder (ADHD), the spontaneously hypertensive rat (SHR), and information obtained from patients with ADHD, suggest a defect in neuronal circuits that are required for reward-guided associative learning and memory formation. Evidence derived from (i). the neuropharmacology of drugs that are effective in treating ADHD symptoms, (ii). molecular genetic and neuroimaging studies of ADHD patients, as well as (iii). the behaviour and biochemistry of animal models, suggests dysfunction of dopamine neurons. SHR have decreased stimulation-evoked release of dopamine as well as disturbances in the regulation of norepinephrine release and impaired second messenger systems, cAMP and calcium. In addition, evidence supports a selective deficit in the nucleus accumbens shell of SHR which could contribute to impaired reinforcement of appropriate behaviour.

Double-blind, placebo-controlled study of zinc sulfate in the treatment of attention deficit hyperactivity disorder

BACKGROUND

The most commonly used medications for attention deficit hyperactivity disorder (ADHD) are the psychostimulants. There is, however, considerable awareness in alternative, nonstimulant therapies, because some patients respond poorly to stimulants or are unable to tolerate them. Some studies suggest that deficiency of zinc play a substantial role in the aetiopathogenesis of ADHD. Therefore, to assess the efficacy of zinc sulfate we conducted treatment trial.

METHODS

Patients with a primary DSM-IV diagnosis of ADHD (N=400; 72 girls, 328 boys, mean age=9.61+/-1.7) were randomly assigned in a 1:1 ratio to 12 weeks of double-blind treatment with zinc sulfate (n=202) (150 mg/day) or placebo (n=198). Efficacy was assessed with the Attention Deficit Hyperactivity Disorder Scale (ADHDS), Conners Teacher Questionnaire, and DuPaul Parent Ratings of ADHD. Primary efficacy variables were differences from baseline to endpoint (last observation carried forward) in mean ADHDS and Conners Teacher Questionnaire scores between the zinc sulfate and the placebo groups. Safety evaluations included monitoring of adverse events, vital signs and clinical laboratory values.

RESULTS

Zinc sulfate was statistically superior to placebo in reducing both hyperactive, impulsive and impaired socialization symptoms, but not in reducing attention deficiency symptoms, as assessed by ADHDS. However, full therapeutic response rates of the zinc and placebo groups remained 28.7% and 20%, respectively. It was determined that the hyperactivity, impulsivity and socialization scores displayed significant decrease in patients of older age and high BMI score with low zinc and free fatty acids (FFA) levels. Zinc sulfate was well tolerated and associated with a low rate of side effect.

CONCLUSIONS

Zinc monotherapy was significantly superior to placebo in reducing symptoms of hyperactivity, impulsivity and impaired socialization in patients with ADHD. Although by themselves, these findings may not be sufficient, it may well be considered that zinc treatment appears to be an efficacious treatment for ADHD patients having older age and high BMI score with low zinc and FFA levels.

Atomoxetine

Atomoxetine (Strattera) is a selective norepinephrine reuptake inhibitor and nonstimulant that has shown greater efficacy than placebo in attention deficit hyperactivity disorder (ADHD) in adults. In two large, well controlled, 10-week trials in adults with ADHD, improvements in ADHD symptoms, as assessed by investigator- and patient-rated scores, were greater with oral atomoxetine (60, 90 or 120 mg/day) than with placebo. Mean reductions in the total ADHD symptom score on the investigator-rated Conners' Adult ADHD Rating Scale (CAARS) in atomoxetine versus placebo recipients were 28.3% versus 18.1% and 30.1% versus 19.6%, respectively. Mean reductions in the scores on the Clinician Global Impression of Severity Scale, patient-rated CAARS and Wender-Reimherr Adult Attention Deficit Disorder Scale were also significantly greater with atomoxetine than with placebo. Continued efficacy was demonstrated in a noncomparative, 34-week extension phase. Atomoxetine was generally well tolerated in clinical trials; withdrawal rates due to adverse events in atomoxetine-treated versus placebo-treated patients participating in the two major trials were 7.8% versus 4.3% and 9.3% versus 2.4% (p<0.05 for the latter trial). Adverse events reported significantly more frequently with atomoxetine than placebo included dry mouth, insomnia, nausea, decreased appetite, constipation, dizziness, sweating, dysuria, sexual problems and palpitations. Modest increases in heart rate and blood pressure were well tolerated and gradually decreased on cessation of treatment. Atomoxetine was not associated with QT interval prolongation. Atomoxetine can be administered once or twice daily. Its subjective-effects profile is different to that of methylphenidate and atomoxetine is not associated with abuse or diversion; it is therefore not a controlled substance in the US. This also means repeat prescriptions during long-term treatment can be more conveniently processed.

CONCLUSION

Atomoxetine is an effective and generally well tolerated treatment for adults with ADHD. It is a nonstimulant and is the first ADHD treatment to be approved specifically for adult use based on its efficacy in well controlled adult trials. It can be administered as a single daily dose or split into two evenly divided doses. It carries negligible risk of abuse or diversion and is not a controlled substance. Atomoxetine is a valuable new treatment option for adults with ADHD and is particularly useful in patients who are at risk for substance abuse or who do not wish to take a controlled substance.

Donepezil in a chronic drug user--a potential treatment?

The objective of the current study was to explore the potential cognitive benefits of an anticholinesterase inhibitor, donepezil, in a former chronic drug user. A neuropsychological test battery composed of the vocabulary and matrix reasoning subtests of the Wechsler adult intelligence scale-III, measures of everyday executive functioning (behavioural assessment of the dysexecutive syndrome [BADS]), and verbal learning and memory tasks (California verbal learning test-II; Rivermead behavioural memory test) was completed at baseline, at 3 months after introducing donepezil, and at 3 months after donepezil was discontinued. After donepezil treatment, substantial improvements were found on tasks of nonverbal fluid reasoning (i.e. matrix reasoning) and other executive functioning tests (i.e. BADS). At entry into the study, poor academic performance and subjective problems with memory and concentration were reported, particularly after amphetamine use (i.e. MDMA and crystal methamphetamine); after donepezil treatment, dramatic increases in memory, concentration and academic achievement were observed. The finding of improvements in tests of executive functioning and in academic performance in this case study, together with the minimal adverse side effects of donepezil, warrants the investigation of controlled studies of cholinergic enhancement in chronic amphetamine and other drug users.

No evidence of attentional deficits in stabilized bipolar youth relative to unipolar and control comparators

OBJECTIVE

The purpose of this study was to determine the presence or absence of attentional problems and prior diagnosis of ADHD in a cohort of stabilized bipolar I relative to unipolar and normal control.

METHOD

Indices of attention were obtained from bipolar (n = 44), unipolar (n = 30), and normal controls (n = 45). Measures included: Freedom from Distractibility (FD) Composite Index of the WISC III, Conners' Continuous Performance Test (CPT), Wisconsin Card Sorting Test (WCST), and a checklist measure of subjective cognitive/attentional problems (SIP-AV).

RESULTS

Bipolar (6.8%), unipolar (10%), and no control youth report a prior diagnosis of ADHD. No significant group or sex differences were observed on FD Composite Index, various CPT indices, or the WCST. Despite normative attentional function by objective testing, subjectively experienced cognitive problems in the clinical probands were reported.

CONCLUSIONS

This cohort of well-functioning bipolar youth diagnosed on average 3-4 years prior to assessment do not possess attentional deficits based on a variety of objective tests compared to unipolar or control youth, but self report subjective difficulties in attentional/problem solving ability. In contrast to other authors, we do not find that bipolar youth have high rates of comorbid ADHD.

Atomoxetine: a selective noradrenaline reuptake inhibitor for the treatment of attention-deficit/hyperactivity disorder

Atomoxetine (Strattera, Eli Lilly & Co.) is a selective noradrenaline reuptake inhibitor that has been studied for use in the treatment of attention-deficit/hyperactivity disorder (ADHD). So far, two open-label and seven randomised, double-blind, placebo-controlled, clinical trials have been published, six in youths and three in adults. Each of these trials has shown a positive response as measured by the primary efficacy measures, the ADHD-IV Rating Scale (ADHD RS) or the Conners Adult ADHD Rating Scale (CAARS). Atomoxetine has generally been well tolerated. In November of 2002 the FDA approved atomoxetine for use in the US for the treatment of ADHD in children, adolescents and adults. Atomoxetine is the first nonstimulant approved by the FDA for the treatment of ADHD and the first medication approved for the treatment of adult ADHD.

Animal models of attention-deficit hyperactivity disorder

Attention-deficit hyperactivity disorder (ADHD) involves clinically heterogeneous dysfunctions of sustained attention, with behavioral overactivity and impulsivity, of juvenile onset. Experimental models, in addition to mimicking syndromal features, should resemble the clinical condition in pathophysiology, and predict potential new treatments. One of the most extensively evaluated animal models of ADHD is the spontaneously hypertensive rat. Other models include additional genetic variants (dopamine transporter gene knock-out mouse, coloboma mouse, Naples hyperexcitable rat, acallosal mouse, hyposexual rat, and population-extreme rodents), neonatal lesioning of dopamine neurons with 6-hydroxydopamine, and exposure to other neurotoxins or hippocampal irradiation. None is fully comparable to clinical ADHD. The pathophysiology involved varies, including both deficient and excessive dopaminergic functioning, and probable involvement of other monoamine neurotransmitters. Improved models as well as further testing of their ability to predict treatment responses are required.

Atomoxetine in adults with ADHD: two randomized, placebo-controlled studies

BACKGROUND

[corrected] Attention-deficit/hyperactivity disorder (ADHD) has been less studied in adults than in children, and the treatment studies reported to date have been small, single-center trials. To assess the efficacy of atomoxetine, a new and highly selective inhibitor of the norepinephrine transporter, we conducted two large, multicenter treatment trials.

METHODS

Two identical studies using randomized, double-blind, placebo-controlled designs and a 10-week treatment period were conducted in adults with DSM-IV-defined ADHD as assessed by clinical history and confirmed by a structured interview (study I, n = 280; study II, n = 256). The primary outcome measure was a comparison of atomoxetine and placebo using repeated measures mixed model analysis of postbaseline values of the Conners' Adult ADHD Rating Scale.

RESULTS

In each study, atomoxetine was statistically superior to placebo in reducing both inattentive and hyperactive and impulsive symptoms as assessed by primary and secondary measures. Discontinuations for adverse events among atomoxetine patients were under 10% in both studies.

CONCLUSION

Atomoxetine appears to be an efficacious treatment for adult ADHD. Its lack of abuse potential may be an advantage for many patients.

Attention-deficit/hyperactivity disorder

Attention-deficit/hyperactivity disorder (ADHD) is one of the most common conditions demanding the time and knowledge of school nurses. Although the condition was identified 100 years ago, it is only in the past decade that information has been clarified. New medication is continually being developed, and the area of comorbidity is exploding. This article updates school nurses on the latest information regarding ADHD.

Childhood mania, attention deficit hyperactivity disorder and conduct disorder: a critical review of diagnostic dilemmas

OBJECTIVES

Significant debate exists on whether early onset bipolar disorder is mistakenly attributed to attention deficit hyperactivity disorder (ADHD) or conduct disorder (CD), or whether ADHD and CD are frequently misdiagnosed as mania. We review the literature on the extent to which these disorders can be reliably differentiated, and describe the diagnostic confusion that may be the result of features common to both classes of disorders.

METHODS

The review focuses on research studies that have examined whether overlapping symptoms of bipolar disorder, ADHD, and CD contribute to misdiagnosis of the two classes of disorders, the prevalence of early onset bipolar disorder with comorbid ADHD or CD, and theories regarding the origins of this comorbidity.

RESULTS

Reliable and accurate diagnoses can be made despite the symptom overlap of bipolar disorder with ADHD and CD. Children with bipolar disorder and ADHD may have a distinct familial subtype of bipolar disorder. Some findings suggest that manic symptoms may represent 'noise' that indicates the general severity of psychopathology in a child or adolescent.

CONCLUSIONS

Further prospective studies may confirm whether early onset bipolarity can be successfully differentiated from ADHD or CD, whether all three types of disorders can be recognized in comorbid cases, or whether comorbid cases represent a distinct subtype of bipolar disorder.

Atomoxetine and methylphenidate treatment in children with ADHD: a prospective, randomized, open-label trial

OBJECTIVE

To assess the comparability of atomoxetine, a new therapy for attention-deficit/hyperactivity disorder (ADHD) and methylphenidate. (Atomoxetine was originally called tomoxetine. The name was recently changed in order to avoid any potential confusion with tamoxifen that might lead to errors in dispensing drug.)

METHOD

Children with ADHD were randomized to open-label atomoxetine or methylphenidate for 10 weeks. Response was assessed with the ADHD-IV Rating Scale.

RESULTS

Two hundred twenty-eight patients were randomized (atomoxetine n = 184, methylphenidate n = 44). Both drugs were associated with marked improvement in inattentive and hyperactive-impulsive symptom clusters as assessed by parents and investigators. No statistically significant differences between treatment groups were observed on the primary outcome measure (investigator-rated ADHD-IV Rating Scale total score: atomoxetine baseline: 39.4 [8.5], endpoint: 20.0 [13.9]; methylphenidate baseline: 37.6 [9.7], endpoint: 19.8 (16.6); p = .66). Safety and tolerability were also similar between the 2 drugs. Discontinuations due to adverse events were 10/184 (5.4%) for atomoxetine and 5/44 (11.4%) for methylphenidate; p = .175.

CONCLUSION

These data provide preliminary evidence that atomoxetine is associated with therapeutic effects comparable to those of methylphenidate.

Effects of norepinephrine and serotonin transporter inhibitors on hyperactivity induced by neonatal 6-hydroxydopamine lesioning in rats

Consistent with their clinical effects in attention deficit-hyperactivity disorder (ADHD), the stimulants methylphenidate and amphetamine reduce motor hyperactivity in juvenile male rats with neonatal 6-hydroxydopamine (6-OHDA) lesions of the forebrain dopamine (DA) system. Since stimulants act on several aminergic neurotransmission systems, we investigated underlying mechanisms involved by comparing behavioral actions of d-methylphenidate, selective inhibitors of the neuronal transport of DA [GBR-12909 (1-[2-[bis(4-fluorophenyl)methoxy]ethyl]-4-[3-phenylpropyl]piperazine dihydrochloride), amfonelic acid], serotonin [5-hydroxytryptamine (5-HT), citalopram, fluvoxamine], and norepinephrine (NE; desipramine, nisoxetine) in 6-OHDA lesioned rats. Selective dopamine lesions were made using 6-OHDA (100 microg, intracisternal) on postnatal day (PD) 5 after desipramine pretreatment (25 mg/kg, s.c.) to protect noradrenergic neurons. Rats were given test agents or vehicle, intraperitoneally, before recording motor activity for 90 min at PD 25 in a novel environment. d-Methylphenidate stimulated motor activity in sham controls and antagonized hyperactivity in lesioned rats. Selective DA transport inhibitors GBR-12909 and amfonelic acid greatly stimulated motor activity in sham control subjects, too, but did not antagonize hyperactivity in lesioned rats. In contrast, all selective 5-HT and NE transporter antagonists tested greatly reduced motor hyperactivity in 6-OHDA lesioned rats but did not alter motor activity in sham controls. The findings indicate that behavioral effects of stimulants in young rats with neonatal 6-OHDA lesions may be mediated by release of NE or 5-HT and support interest in using drugs that increase activity of norepinephrine or serotonin to treat ADHD.

The future of pharmacotherapy for paediatric anxiety

There is a growing body of data supporting the use of pharmacological agents in the treatment of paediatric anxiety. The most compelling data exists for the use of selective serotonin re-uptake inhibitors. However, questions the safe and efficacious use of medications with anxiolytic properties still remain. Although the field has progressed in the past several years, it is evident that more research needs to be done in the future.

Attention deficit hyperactivity disorder (ADHD) and substance use disorders

Attention deficit hyperactivity disorder (ADHD) is a common childhood disorder that often continues to manifest symptoms into adulthood. In children and adults, this condition may contribute to addictive vulnerability. Several factors are common to the developmental psychopathology of these conditions, suggesting an underlying deficit in behavioral regulation as an explanation for this comorbidity. Developmentally, faulty learning processes or attempts to self-medicate dysfunctional behavior may contribute to the pathogenesis of substance use disorders. Substance abuse itself also may contribute to the development of attentional deficits and behavioral dysregulation through direct (eg, prenatal or self-inflicted exposures to neurotoxic substances) and indirect (eg, poverty, neglect, abuse) mechanisms. Because ADHD can be identified prior to the peak onset of substance use, effective treatment of this common disorder may reduce the development of substance use disorders. Adult ADHD may also contribute to the development and maintenance of substance use disorders Substance abuse patients may particularly benefit from treatment of this comorbidity.

Present and future pharmacotherapeutic options for adult attention deficit/hyperactivity disorder

Attention deficit/hyperactivity disorder (ADHD) is often a lifelong condition. When untreated or undertreated, it appears to have a deleterious impact upon the daily functioning of the majority of adults that were diagnosed with this condition during childhood. Effective treatment, under the best circumstances, is multi-modal. The recent MTA study staged by the United States government confirmed the primary role of psychostimulants for children with this condition. The findings from this study have been generalised to adults that also have ADHD, particularly in cases where there is a well-defined longitudinal history dating back to early childhood. Psychostimulants remain a viable first-choice strategy for adults with ADHD. There are idiosyncratic differences in response to the various psychostimulants for any given individual with ADHD. Furthermore, the emergence of long-acting, once daily psychostimulant medications is likely to improve the calibre of care for adults with ADHD. A number of alternative pharmacotherapies have been studied, or are being developed, for adults with ADHD. These pharmacotherapies include antidepressant medications that affect dopaminergic and noradrenergic bioavailability, as well as cholinergic agents. In addition, agents that manipulate histaminergic and glutaminergic receptors are being studied as possible non-stimulant alternatives in the management of adult ADHD. More information is needed before any definitive statements can be made concerning the feasibility and utility of these non-stimulant medication approaches.

Treatment of attention-deficit hyperactivity disorder

Attention-deficit hyperactivity disorder (ADHD) is a common disorder among children and adolescents with reported prevalence rates of between 3 and 10%. Recent reports suggest that a multimodal treatment approach is preferable to address many symptoms of ADHD and its associated problems for the children, the family, and the school. Stimulant medications remain the mainstay of treatment and are highly effective in more than 75% of patients. Improvement in the core symptoms of inattention, impulsivity, and hyperactivity are most noticeable. Recently approved extended release preparation of methylphenidate will allow once a day dosing. Reports of effectiveness of some non-stimulant medications such as bupropion, especially for adolescents, appear promising. A number of behavioral and psychosocial interventions can be used effectively as part of multimodal approach to address many ADHD-related problems. This article provides an update on practical information on the treatment of children and adolescents with ADHD who do not have other associated psychiatric disorders.