Enantioselective hydrolysis of oral racemic methylphenidate (dl-MPH) by carboxylesterase 1 (CES1) limits the absolute bioavailability of the pharmacologically active d-MPH isomer to approximately 30% and that of the inactive l-MPH to only 1-2%. Coadministration of dl-MPH with ethanol results in elevated d-MPH plasma concentrations accompanied by CES1-mediated enantioselective transesterificatio...

OBJECTIVES To evaluate the prevalence of methylphenidate (MPH) use among 5th and 6th year medical students, to discriminate MPH use with and without medical indication, and to correlate MPH use with alcohol intake. METHODS This is a cross-sectional study in which medical students were invited to answer a questionnaire to evaluate academic and socioeconomic status, MPH use patterns, and attitu...

BACKGROUND Attention-deficit/hyperactivity disorder (ADHD) symptoms are most commonly treated with stimulant medication such as methylphenidate (MPH); however, approximately 25% of patients show little or no symptomatic response. We examined the extent to which initial changes in brain functional connectivity (FC) associated with the first MPH dose in boys newly diagnosed with ADHD predict MPH-...

Attention deficit hyperactivity disorder (ADHD) is one of the most prevalent neuropsychiatry disorders in children and adolescents, and methylphenidate (MPH) is a first-line stimulant drug available worldwide for its treatment. Despite the proven therapeutic efficacy, concerns have been raised regarding the possible consequences of chronic MPH exposure during childhood and adolescence. Disturba...

Abstract Background Attention-deficit hyperactivity disorder (ADHD) is a commonly diagnosed behavioral in school-aged children. A core symptom of ADHD difficulties with executive functions (EF). Physical activity (PA) interventions are proposed to be valuable addition traditional treatment approaches for ADHD. This systematic review examined the evidence effect chronic PA on EF, specifically, i...

Methylphenidate (MPH) is the active ingredient in Ritalin, although effective treating ofthe attention deficit hyperactivity disorder (ADHD), its neurostimulation action attractiveamong students order to increase focus or improving student performance. In context Developmental Origins of Health and Disease (DOHaD) concept, states that insults incritical phases development, as peripubertal perio...

Methylphenidate (MPH) often ameliorates attention-deficit/hyperactivity disorder (ADHD) behavioral dysfunction according to indirect informant reports and rating scales. The standard of care behavioral MPH titration approach seldom includes direct neuropsychological or academic assessment data to determine treatment efficacy. Documenting "cool" executive-working memory (EWM) and "hot" self-regu...

PURPOSE To assess clinical findings of eye examination in children having attention deficit hyperactivity disorder (ADHD) administered with methylphenidate hydrochloride. METHODS Fifty-seven consecutive patients diagnosed of ADHD and administered with oral methylphenidate hydrochloride treatment for at least one year were involved in this study (Group 1). Sixty healthy subjects (Group 2) havi...

An HPLC-peroxyoxalate chemiluminescence (PO-CL) method for simultaneous determination of methylphenidate (MPH) and ritalinic acid (RA) was developed. The method was used to monitor MPH and RA after administration of MPH to rats. Deproteinized plasma spiked with 1-(3-trifluoromethylphenyl)piperazine (IS) was dried and labeled with 4-(N,N-dimethylaminosulfonyl)-7-fluoro-2,1,3-benzoxadiazole (DBD-...

WE AIMED TO INVESTIGATE THE EFFECTS OF METHYLPHENIDATE (MPH) IN HEALTHY RATS ON TWO DISTINCT RADIAL MAZE TASKS WHICH RELY ON BRAIN STRUCTURES AND NEUROTRANSMITTERS KNOWN TO BE AFFECTED BY MPH: the Random Foraging Non-Delay Task (RFNDT) and the Delayed Spatial Win Shift Task (DSWT). Hooded Lister rats were trained to complete either the RFNDT or the DSWT having received oral treatment of either ...