Modafinil film-coated tablets in children and adolescents with attention-deficit/hyperactivity disorder: results of a randomized, double-blind, placebo-controlled, fixed-dose study followed by abrupt discontinuation.
ABSTRACT The objective of this fixed-dose study was to determine the efficacy and safety of a new formulation of modafinil (modafinil film-coated tablets) in children and adolescents with attention-deficit/hyperactivity disorder (ADHD). In addition, the effect of abrupt discontinuation of modafinil was evaluated in a 2-week observation period.
Patients aged 6 to 17 years with DSM-IV-TR-defined ADHD were randomly assigned to 7 weeks of double-blind treatment with modafinil or placebo in a 2:1 ratio, followed by abrupt discontinuation of modafinil and a 2-week, double-blind observation period in which 46% of patients receiving modafinil were switched to placebo without tapering and half continued to receive modafinil. Study drug was administered once daily and titrated over the first 7 to 9 days to daily doses of 340 mg for patients < 30 kg or 425 mg for patients > or = 30 kg. Assessment instruments included the Attention-Deficit/ Hyperactivity Disorder Rating Scale-IV (ADHD-RS-IV) School and Home Versions and Clinical Global Impressions-Improvement scale (CGI-I). The study was conducted from November 2003 to June 2004.
A total of 190 patients were randomly assigned to receive modafinil (340 mg, N = 44; 425 mg, N = 82) or placebo (N = 64). 189 patients were evaluated for safety. Modafinil significantly improved symptoms of ADHD as shown by reductions in ADHD-RS-IV School Version total scores compared with placebo at all visits (p < or = .009), including the final visit of the double-blind phase (p < .0001). With modafinil, ADHD-RS-IV School Version mean total scores changed from 37.8 at baseline to 29.3 at week 1 and 20.7 at final visit; corresponding placebo values were 36.6, 32.8, and 28.4, respectively; effect size at final visit was 0.76 (95% CI = 0.63 to 0.88). Total scores on the ADHD-RS-IV Home Version were also significantly reduced at all visits (p < or = .022) and final visit (p = .001) in patients receiving modafinil compared with those receiving placebo. Significantly higher proportions of patients receiving modafinil were rated "much improved" or "very much improved" in overall clinical condition (CGI-I) at all visits compared with patients receiving placebo (p < .001). No withdrawal symptoms were observed when modafinil was abruptly discontinued at the beginning of the final 2-week observation period. Modafinil was generally well tolerated. Insomnia, headache, and decreased appetite were the most commonly reported adverse events. Sixty-three percent of patients who received modafinil completed the study; 13% discontinued because of lack of efficacy; 10%, because of adverse events; and 13%, for other reasons (e.g., consent withdrawn, lost to follow-up).
Modafinil significantly improved symptoms of ADHD both at school and at home and was well tolerated by children and adolescents. Abrupt discontinuation of modafinil was not associated with symptoms of withdrawal or with rebound of symptoms of ADHD.
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ABSTRACT: Psychostimulants such as cocaine have been used as performance enhancers throughout recorded history. Although psychostimulants are commonly prescribed to improve attention and cognition, a great deal of literature has described their ability to induce cognitive deficits, as well as addiction. How can a single drug class be known to produce both cognitive enhancement and impairment? Properties of the particular stimulant drug itself and individual differences between users have both been suggested to dictate the outcome of stimulant use. A more parsimonious alternative, which we endorse, is that dose is the critical determining factor in cognitive effects of stimulant drugs. Herein, we review several popular stimulants (cocaine, amphetamine, methylphenidate, modafinil, and caffeine), outlining their history of use, mechanism of action, and use and abuse today. One common graphic depiction of the cognitive effects of psychostimulants is an inverted U-shaped dose-effect curve. Moderate arousal is beneficial to cognition, whereas too much activation leads to cognitive impairment. In parallel to this schematic, we propose a continuum of psychostimulant activation that covers the transition from one drug effect to another as stimulant intake is increased. Low doses of stimulants effect increased arousal, attention, and cognitive enhancement; moderate doses can lead to feelings of euphoria and power, as well as addiction and cognitive impairment; and very high doses lead to psychosis and circulatory collapse. This continuum helps account for the seemingly disparate effects of stimulant drugs, with the same drug being associated with cognitive enhancement and impairment.Pharmacological reviews 01/2014; 66(1):193-221. DOI:10.1124/pr.112.007054 · 18.55 Impact Factor
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ABSTRACT: Survivors of childhood cancer frequently experience cancer-related cognitive dysfunction, commonly months to years after treatment for pediatric brain tumors, acute lymphoblastic leukemia (ALL), or tumors involving the head and neck. Risk factors for cancer-related cognitive dysfunction include young age at diagnosis, treatment with cranial irradiation, use of parenteral or intrathecal methotrexate, female sex, and pre-existing comorbidities. Limiting use and reducing doses and volume of cranial irradiation while intensifying chemotherapy have improved survival and reduced the severity of cognitive dysfunction, especially in leukemia. Nonetheless, problems in core functional domains of attention, processing speed, working memory and visual-motor integration continue to compromise quality of life and performance. We review the epidemiology, pathophysiology and assessment of cancer-related cognitive dysfunction, the impact of treatment changes for prevention, and the broad strategies for educational and pharmacological interventions to remediate established cognitive dysfunction following childhood cancer. The increased years of life saved after childhood cancer warrants continued study toward the prevention and remediation of cancer-related cognitive dysfunction, using uniform assessments anchored in functional outcomes.JNCI Journal of the National Cancer Institute 08/2014; 106(8). DOI:10.1093/jnci/dju186 · 15.16 Impact Factor
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ABSTRACT: Seizures occur when the excitability of brain circuits is not sufficiently restrained by inhibitory mechanisms. Although modafinil is reported to reduce GABA-activated currents and extracellular GABA levels in the brain, the drug exerts anticonvulsant effects in animal studies. The aim of this study was to determine the effects of modafinil and its metabolites (sulfone and carboxylic acid) on the anticonvulsant action of four classical antiepileptic drugs (AEDs)-carbamazepine (CBZ), phenobarbital (PB), phenytoin (PHT), and valproate (VPA). Anticonvulsant activity was assessed with the maximal electroshock seizure threshold (MEST) test and MES test in mice. Brain concentrations of AEDs were measured to ascertain any pharmacokinetic contribution to the observed anticonvulsant effects. Intraperitoneal injection of 75 mg kg(-1) of modafinil or its metabolites significantly elevated the threshold for electroconvulsions in mice, whereas 50 mg kg(-1) of each compound enhanced the anticonvulsant activity of CBZ, PHT, and VPA, but not that of PB. A 25-mg kg(-1) dose of modafinil or its sulfone metabolite enhanced anticonvulsant activity of VPA. Modafinil and its metabolites (50 mg kg(-1)) did not alter total brain concentrations of PB and VPA but did elevate CBZ and PHT. Enhancement of anticonvulsant actions of VPA by modafinil in the mouse MES model is a pharmacodynamic effect. Collectively, our data suggest that modafinil may be a safe and beneficial adjunct to the therapeutic effects of AEDs in human patients.Psychopharmacology 02/2015; DOI:10.1007/s00213-015-3884-3 · 3.99 Impact Factor