PubMed Health⌕ Search

PubMed · 12215063

Dexmethylphenidate.

Abstract

Dexmethylphenidate comprises only the d-enantiomer (the pharmacologically effective isomer) of racemic methylphenidate and is indicated for the treatment of patients aged > or =6 years with attention deficit hyperactivity disorder (ADHD). In a 4-week, double-blind trial in 132 children with ADHD, significantly greater improvements from baseline in teacher-rated Swanson, Nolan and Pelham (SNAP)-ADHD scores were seen in dexmethylphenidate and methylphenidate recipients, compared with placebo recipients. In addition, significantly more dexmethylphenidate and methylphenidate recipients, compared with placebo recipients, were much improved or very much improved according to Clinical Global Impression-Improvement of Illness scale scores. In the same study, parent-rated SNAP-ADHD scores had decreased by a significantly greater extent in dexmethylphenidate recipients at 3pm and 6pm and in methylphenidate recipients at 3pm, compared with placebo recipients. Significantly fewer dexmethylphenidate than placebo recipients failed treatment in a double-blind, treatment-withdrawal trial in 75 children with ADHD (17.1 vs 61.5%). In a noncomparative study in 22 children with ADHD, symptoms of ADHD, as assessed by teachers and parents, were controlled during the entire school day in 68 and 86% of dexmethylphenidate recipients, respectively, with a median duration of effect of 6.3 and 7.5 hours, respectively. Dexmethylphenidate was generally well tolerated in children with ADHD; adverse events were consistent with those known to be associated with agents containing methylphenidate.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Gillian M Keating, David P Figgitt. 2002. Dexmethylphenidate.. https://doi.org/10.2165/00003495-200262130-00009

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

Structure and composition of silicon-stabilized tricalcium phosphate.

Silicon stabilized tricalcium phosphate [Si-TCP] is formed within the calcium hydroxyapatite (HA)-tricalcium phosphate (TCP) system when a stoichiometric precipitate of hydroxyapatite is fired at 1,000 degrees in the presence of SiO(2). This paper proposes a composition range and crystallographic structure for Si-TCP. Reitveld XRD powder diffraction, transmission electron microscopy, infrared and proton nuclear magnetic resonance measurements show that crystalline Si-TCP is associated with the displacement of OH from an initial hydroxyapatite structure. The resulting calcium phosphate is modified by the incorporation of silicon into its structure with excess silica contributing to an amorphous component. Si-TCP has a monoclinic structure with a space group P2(1)/a akin to alpha-TCP with estimated lattice constants of a=12.863+/-0.004 A, b=9.119 +/-0.003 A, c=15.232+/-0.004 A, beta=126.3+/-0.1 degrees. It is proposed that Si(4+) substitutes for P(5+)in the TCP lattice with the average chemical composition of Si-TCP set primarily by the mechanisms available for charge compensation. While the formation of OH vacancies in HA initiates the transformation to Si-TCP, two mechanisms of charge compensation in the Si-TCP structure are plausible. If O(2-) vacancies provide charge compensation, the composition of Si-TCP is Ca(3)(P(0.9)Si(0.1)O(3.95))(2) derived for the addition of 0.33 mol SiO(2):mol HA. If excess Ca(2+) compensates, the composition is Ca(3.08)(P(0.92)Si(0.08)O(4))(2) derived for the addition of 0.25 mol SiO(2):mol HA. The reaction occurs most effectively when SiO(2) is added as a colloidal suspension rather than by the in-situ thermal decomposition of a silicon metallorganic compound. The material is a bioceramic of major biological interest because of its osteoconductivity and unique influence on skeletal tissue repair and remodeling.

Absorption↗

The puzzle of where cerebrospinal fluid is absorbed: new pieces.

The widely held theory of cerebrospinal fluid (CSF) absorption by the arachnoid villus system cannot explain the movement of substances within the fluid, the deposition pattern of corpora amylacea on the surface of the brain, and pathological findings in neurological disorders. Experiments studying the movement of melatonin and inulin in the CSF compartment demonstrate that some CSF recycles into the ventricular system and CSF contacting tissue diffusely absorbs some. Photomicrographs of a suprapineal recess portal into the third ventricle are presented. A cycling theory of CSF assigns function to the structure of the choroid fissures and the suprapineal recess.

Absorption↗

Development of enzyme-linked immunosorbent assay for evaluation of chapati-making quality of wheat varieties.

An indirect enzyme-linked immunosorbent assay (ELISA) has been developed for evaluation of chapati-making quality of wheat varieties. Polyclonal antibodies against gliadin, low molecular weight glutenin (LMG), and high molecular weight glutenin (HMG) were developed and utilized in the ELISA. Twenty-eight Indian wheat varieties were utilized in the ELISA. Out of these antibodies, an antigliadin antibody response was negatively correlated with farinograph water absorption (r = -0.89 at P < 0.01), chapati dough water absorption (r = -0.91 at P < 0.01), overall chapati sensory score (r = -0.95 at P < 0.01), chapati puffed height score (r = -0.95 at P < 0.01), and positively correlated with shear value of chapati (r = 0.76 at P < 0.01). Anti-LMG antibody response was not correlated with any of these parameters, whereas anti-HMG response positively correlated with chapati dough water absorption (r = 0.44 at P < 0.05), farinograph water absorption (r = 0.45 at P < 0.05), and overall chapati sensory score (r = 0.44 at P < 0.05), and negatively correlated with shear value (r = -0.38 at P < 0.05) and chapati puffed height (r = -0.44 at P < 0.05). The results indicate that wheat varieties with good chapati-making quality were having less antigliadin antibody response.

Absorption↗