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PubMed1997

Methylphenidate patterns among Medicaid youths.

Treatment of attentional disorders in America has increased dramatically in recent years. This trend is accounted for partly by lengthening the duration of treatment into adulthood for some individuals as well as by increased treatment among girls. Beyond these factors, the role of economic status, race, and geographic region to explain the variation in methylphenidate use is not well understood. Computerized administrative data were used to explore the influence of several sociodemographic factors on the prevalence of methylphenidate use. The data source consisted of Maryland Medicaid prescription drug reimbursement claims data for FY1991 for children ages 5 to 14 years. In effect, the study was restricted to a sample of patients with limited income. The study aims included (1) measuring gender-, age-, race-, and region-specific methylphenidate prevalence for this restricted income population; (2) comparing the Caucasian:African-American (C:A-A) ratio for methylphenidate with the C:A-A ratio for several drug therapies having non-psychotropic uses, specifically the anti-asthma drug, theophylline, and antibiotics for infections; and (3) estimating the average daily dose of methylphenidate from prescription claims data. Total drug-specific prevalence among the 5-14 year olds was 2.2 percent for methylphenidate while age-specific prevalence varied from 0.4 percent (5 year olds) to 3.4 percent (9 year olds). The gender ratio was 3.7:1 (M:F), confirming the increasing trend for girls to receive this medication. Substantial variation across eight defined regions of the state was observed. Racial differences were pronounced: African-Americans were 2.5 times less likely to receive methylphenidate than Caucasian youths. As hypothesized, non-psychotropic drug use was distinctly different from psychotropic drug use in terms of race: theophylline was 1.5 times more likely to be found for African-Americans than Caucasians, whereas antibiotic prescriptions were 1.5 times more likely to be prescribed to Caucasian youths. Average daily dose of methylphenidate was estimated to be 18.7 +/- 10.4 mg for 5-9 year olds and 26.8 +/- 14.0 mg for 10-14 year olds. This brief report confirms the typically lower rate among African-American Medicaid youths for most prescription drugs. The dramatic racial disparity for the psychotropic agent methylphenidate is a new and compelling finding which should be verified among other economic groups. Diagnostic, referral, and cultural bias should be ruled out as possible explanations for the observed differences.

Adolescent↗
PubMed2005

Randomized, controlled, crossover trial of methylphenidate in pervasive developmental disorders with hyperactivity.

CONTEXT: Hyperactivity and inattention are common symptoms in children with autistic disorder and related pervasive developmental disorders, but studies of stimulants in these conditions have been inconclusive. OBJECTIVES: To determine the efficacy and safety of methylphenidate hydrochloride in children with pervasive developmental disorders and hyperactivity. DESIGN: Double-blind, placebo-controlled, crossover trial followed by open-label continuation. SETTING: Five academic outpatient clinics. PARTICIPANTS: Seventy-two drug-free children, aged 5 to 14 years, with pervasive developmental disorders accompanied by moderate to severe hyperactivity. INTERVENTIONS: Prior to randomization, subjects entered a 1-week test-dose phase in which each subject received placebo for 1 day followed by increasing doses of methylphenidate (low, medium, and high doses) that were each given for 2 days. The low, medium, and high doses of methylphenidate hydrochloride were based on weight, and they ranged from 7.5 mg/d to 50.0 mg/d in divided doses. Subjects who tolerated the test dose (n = 66) were assigned to receive placebo for 1 week and then 3 methylphenidate doses in random order during a double-blind, crossover phase. Children responding to methylphenidate then entered 8 weeks of open-label treatment at the individually determined best dose. MAIN OUTCOME MEASURES: The primary outcome measure was the teacher-rated hyperactivity subscale of the Aberrant Behavior Checklist. Response was defined as "much improved" or "very much improved" on the Clinical Global Impressions Improvement item coupled with considerable reductions in the parent-rated and/or teacher-rated Aberrant Behavior Checklist hyperactivity subscale score. RESULTS: Methylphenidate was superior to placebo on the primary outcome measure, with effect sizes ranging from 0.20 to 0.54 depending on dose and rater. Thirty-five (49%) of 72 enrolled subjects were classified as methylphenidate responders. Adverse effects led to the discontinuation of study medication in 13 (18%) of 72 subjects. CONCLUSIONS: Methylphenidate was often efficacious in treating hyperactivity associated with pervasive developmental disorders, but the magnitude of response was less than that seen in typically developing children with attention-deficit/hyperactivity disorder. Adverse effects were more frequent.

Adolescent↗
PubMed2000

Effect of food on the pharmacokinetics of osmotic controlled-release methylphenidate HCl in healthy subjects.

The effect of a high-fat meal on the pharmacokinetics of OROS(R) (methylphenidate HCl), an osmotic controlled-release formulation of methylphenidate HCl, was investigated in healthy subjects. Mean peak methylphenidate plasma concentrations occurred slightly later and peak methylphenidate plasma concentrations and AUC values were slightly higher (approximately 10-30%) in the presence of food than in the absence of food. There was no difference in the plasma elimination half-life of methylphenidate between the fed and fasted state. Similarly, peak concentrations and AUC values for alpha-phenyl-2-piperidine acetic acid (PPA; ritalinic acid), the major metabolite of methylphenidate, were slightly higher in the presence of food than in its absence. The 90% confidence interval (CI) for the treatment ratio (fed/fasted) for C(max) was 120.6%-140. 0% for the 18-mg dose and 105.4-119.3% for a 36-mg dose. The 90% CI for the treatment ratio for AUC(infinity) was 114.6-125.7% for the 18-mg dose and 115.1-124.6% for the 36-mg dose. PPA levels were measured following the 18-mg dose and the 90% CI of the treatment ratio was 106.8-115.4% for C(max) and 97.9-103.6% for AUC(infinity). These results indicate the absence of dose dumping from OROS (methylphenidate HCl) in the presence of food. Food does not impede drug absorption and OROS (methylphenidate HCl) may be administered in the fed or fasted state. There were no differences in the adverse event profile between the fed and fasted state.

Administration, Oral↗
PubMed1989

Enantioselective aspects of the disposition of dl-threo-methylphenidate after the administration of a sustained-release formulation to children with attention deficit-hyperactivity disorder.

It has been shown previously that immediate-release dl-threo-methylphenidate (Ritalin) undergoes stereoselective disposition in human adults as well as in children with attention deficit-hyperactivity disorder. Although the sustained-release formulation of dl-threo-methylphenidate (Ritalin-SR) has been demonstrated to be effective in sustaining the attention of the children with attention deficit-hyperactivity disorder, there are no data on plasma levels of methylphenidate after administration of the sustained-release formulation. The purpose of this present investigation was twofold: (1) to determine whether the levels of methylphenidate were sustained for over a time period of 8 h, and (2) to examine enantioselective aspects of the pharmacokinetics following the ingestion of the sustained-release formulation. Six children with attention deficit-hyperactivity disorder were given 20 mg of sustained-release dl-threo methylphenidate. Plasma samples were harvested for a period up to 12 h following ingestion of the drug. The levels of both the enantiomers were sustained for a period of 8 h (the plasma levels of d-methylphenidate were 8- to 10-fold higher than those of the l-enantiomer in the profiles of all six children). Mean areas under the plasma level time curves were 132.78 +/- 92.47 ng.h/mL for d-methylphenidate and 12.73 +/- 7.37 ng.h/mL for l-methylphenidate. The values of oral clearance and apparent volume of distribution calculated for l-enantiomer were higher than the corresponding values for the d-antipode.

Adolescent↗
PubMed2002

Relationship between blockade of dopamine transporters by oral methylphenidate and the increases in extracellular dopamine: therapeutic implications.

Methylphenidate (Ritalin) is an effective drug in the treatment of attention deficit hyperactivity disorder. However, the doses required therapeutically vary significantly between subjects and it is not understood what determines these differences. Since methylphenidate's therapeutic effects are in part due to increases in extracellular DA secondary to blockade of dopamine transporters (DAT), the variability could reflect differences in levels of DAT blockade. Here we used PET to assess if for a given dose of methylphenidate the differences in DAT blockade account for the variability in methylphenidate-induced increases in extracellular DA. Ten healthy adult subjects were tested before and 60 min after oral methylphenidate (60 mg) with PET to estimate DAT occupancy (with [(11)C]cocaine as the radioligand) and levels of extracellular DA (with [(11)C]raclopride as the D2 receptor radioligand that competes with endogenous DA for binding to the receptor). Methylphenidate significantly blocked DAT (60 +/- 11%) and increased extracellular DA in brain (16 +/- 8% reduction in [(11)C]raclopride binding in striatum). However, the correlation between methylphenidate-induced DAT blockade and DA increases was not significant. These results indicate that for a given dose of methylphenidate, individual differences in DAT blockade are not the main source for the intersubject variability in MP-induced increases in DA. This finding suggests that individual differences in response to MP are due in part to individual differences in DA release, so that for an equivalent level of DAT blockade, MP would induce smaller DA changes in subjects with low than with high DA cell activity.

Administration, Oral↗
PubMed1993

Nonlinear kinetics of threo-methylphenidate enantiomers in a patient with narcolepsy and in healthy volunteers.

We have studied the pharmacokinetics of methylphenidate enantiomers after the oral administration of different doses of racemic methylphenidate to one patient with narcolepsy and to four healthy volunteers. The plasma concentrations of (+)-methylphenidate were much higher than those of (-)-methylphenidate after each dose in all subjects. In the patient the oral clearance (CL/f) of (+)-methylphenidate fell 3-fold and the area under the concentration-time curve (AUC) rose 7-fold when the dose was increased from 20 to 40 mg (from 0.27 to 0.53 mg.kg-1), in spite of the relatively constant terminal half-life of 2.6-2.7 h. Similar dose-dependency was also observed in the healthy volunteers in the dose range of 10-60 mg (0.12-0.77 mg.kg-1). The mean value of CL/f for the 40 mg dose was significantly lower than that for the 20 mg dose. The mean AUC of the (+)-isomer corrected to a dose of 10 mg increased significantly between the 20 mg and 40 mg doses. In the urine (+)- and (-)-ritalinic acid were excreted for 48 h after each dose as 32-37% and 34-40% of the dose respectively. The mean total recoveries (sum of enantiomers of methylphenidate and its metabolite, ritalinic acid) in the urine were relatively constant (63-78% of the doses), suggesting that the changes in AUC with dose may not be due to a change in the intestinal absorption of racemic methylphenidate. We conclude that the nonlinear kinetics of (+)-methylphenidate may be due to saturation of its presystemic elimination.

Administration, Oral↗
PubMed1976

Relative efficacy of methylphenidate and behavior modification in hyperkinetic children: an interim report.

Children reported to be hyperactive in school and with behavior difficulties at home were randomly assigned to methylphenidate, behavior therapy and placebo, or behavior therapy with methylphenidate for an 8-week period. Rating scales were obtained from teachers and parents. Independent blind observers rated childrens' classroom bheavior on a weekly basis. A behavior therapy program was implemented in the home and at school. Methylphenidate dosage was individualized. Ratings of behavior deviance were significantly reduced by all treatments. However, a significant advantage for the groups receiving methylphenidate was found over the group receiving behavior therapy and placebo. No significant differences between methylphenidate alone and methylphenidate combined with behavior therapy were obtained. Global ratings of improvement done by teachers favored the combined treatment of behavior therapy and methylphenidate over behavior therapy and placebo. No differences among treatments were found in the mothers' global ratings of improvement. The results indicate that though all three treatments were effective, methylphenidate was significantly superior to behavior therapy alone.

Attention↗
PubMed2004

Neurocognitive effects of methylphenidate in adult attention-deficit/hyperactivity disorder.

RATIONALE: Features of childhood attention-deficit/hyperactivity disorder (ADHD) often persist into adulthood. It has been shown that adult ADHD is associated with various neurocognitive deficits, including impairments in spatial working memory (SWM) and attention. It is not known whether these deficits are ameliorated by methylphenidate in adult ADHD. OBJECTIVES: The aim of this study was to evaluate the neurocognitive effects of a single dose of methylphenidate on SWM, visual memory, spatial span and sustained attention in adult ADHD. METHODS: Twenty-four adult patients, recruited from a specialised clinic for the assessment of adult ADHD, were entered into a double-blind, randomised, placebo-controlled crossover study using a single 30 mg dose of methylphenidate. RESULTS: Eighteen patients met DSM-IV criteria for adult ADHD. Methylphenidate resulted in an improvement in SWM performance and sustained attention, together with a speeding in response time, in these patients. Six patients with attentional difficulties, who did not meet a DSM-IV diagnosis of ADHD, showed a different pattern of response to methylphenidate compared to the ADHD group. For the combined group, moderate correlations were shown between childhood ratings of ADHD (both self-reported and informant ratings) and response to methylphenidate on the SWM task. CONCLUSIONS: Adults with ADHD had a similar neurocognitive response to methylphenidate to that previously reported for childhood ADHD. Our results provide further support for the validity of the ADHD syndrome as defined by DSM-IV and indicate possible neurocognitive substrates for clinical improvement with chronic methylphenidate.

Adult↗
PubMed2005

Behavioural and pharmacological magnetic resonance imaging assessment of the effects of methylphenidate in a potential new rat model of attention deficit hyperactivity disorder.

RATIONALE: The psychomotor stimulant methylphenidate is used in the treatment of attention deficit hyperactivity disorder (ADHD). Whereas the mechanism is not fully understood it is suggested to involve restoration of impaired dopamine function found in ADHD. OBJECTIVES: The aim of this study was to determine the effects of methylphenidate on brain region activation in vivo using pharmacological magnetic resonance imaging (phMRI) in a potential rat model of ADHD. METHODS: Rats were treated bi-daily [from postnatal day (PND) 24] for 4 days with the dopamine re-uptake inhibitor GBR 12909 (30 mg/kg i.p) or vehicle (control). On PND 57 rats were administered methylphenidate (4 mg/kg i.p) and locomotor activity measured. In a separate group of animals, blood oxygen level dependent (BOLD) response was measured using phMRI to determine changes in brain region activation produced by methylphenidate (4 mg/kg i.p.) in GBR 12909-pretreated or control rats. RESULTS: Methylphenidate produced a greater locomotor-stimulant response in controls compared with GBR 12909 rats. Pretreatment with GBR 12909 reduced the BOLD response produced by methylphenidate compared with that in control animals. The main effects of methylphenidate on the BOLD response were seen in the caudate, frontal cortex, hippocampus and hypothalamus. CONCLUSIONS: Short-term treatment with GBR 12909 in young rats causes long-term changes in dopaminergic systems, altering the methylphenidate-induced behavioural response and brain region activation compared with that in vehicle-pretreated rats. The results further support the view that altered dopaminergic function may be an important factor in ADHD and the value of animal models with this functional neurochemical deficit.

Analysis of Variance↗
PubMed2005

Methylphenidate: use in daily practice.

OBJECTIVE: With the aim of getting more insight into compliance of children using methylphenidate, we studied the day-to-day use of the drug. In addition, the efficacy and side effects of treatment, stopping, switching to other drugs and the use of additional psychoactive drugs in daily practice were studied. METHOD: On the basis of pharmacy records, the use of methylphenidate by 52 children was studied. Two parameters for compliance were calculated. By means of a questionnaire, parents were asked about their children's compliance with the use of methylphenidate as well as about their experience with treatment. MAIN OUTCOME MEASURE: Compliance, use of methylphenidate in weekends and holidays, self-reported efficacy, side effects, stopping and switching to other drugs. RESULTS: Depending on the parameter calculated, the percentage of children with a good compliance varied from 25 to 47%. About 65% of the children used less or no methylphenidate in the weekends and holidays. Sixty-five percent of the parents reported to pass over a dose once in a while. According to 61% of the parents (n = 28) the efficacy of methylphenidate was good or very good. Nine (33%) of 28 children stopped using methylphenidate. Seven children stopped using the drug because of side-effects or lack of efficacy. Seven children switched to other psychoactive drugs. Fifty-seven percent of all children used additional psychoactive drugs. CONCLUSION: The percentage of children having a good compliance calculated on the basis of pharmacy records is rather low. This is partly the result of the decreased use of methylphenidate in the weekends and holidays.

Adolescent↗
PubMed1988

Electrophysiological effects of methylphenidate on the coeruleo-cortical noradrenergic system in the rat.

The effect of methylphenidate on noradrenergic neurotransmission was investigated in urethane-anesthetized rats. The spontaneous activity of locus coeruleus noradrenergic neurons was the same in rats treated for 7 days with methylphenidate as in the controls. In control rats, i.v. methylphenidate induced a reduction of locus coeruleus neuronal firing whereas in rats treated for 7 days with methylphenidate, the same dose of methylphenidate failed to induce any change in locus coeruleus activity. At this time, clonidine induced a lesser reduction of locus coeruleus neuronal firing than in the controls, indicating that their autoreceptors had become desensitized. Following electrical stimulation of the locus coeruleus, most of the spontaneously firing cortical neurons were inhibited but the percentage of such neurons was reduced and the neurons showed a decreased responsiveness after methylphenidate treatment. The responsiveness of cortical neurons to microiontophoretic applications of NA as assessed by the I.T50 method was reduced after 7 days of treatment with methylphenidate. These findings suggest that the efficacy of cortical NA neurotransmission is markedly reduced following methylphenidate treatment.

Animals↗
PubMed1996

Methylphenidate effect on attention deficit in the acutely brain-injured adult.

OBJECTIVES: To determine the efficacy of methylphenidate in improving attention and functional outcome in acutely brain-injured adults. DESIGN: Prospective multiple baseline design (A-A-B-A) utilized on a consecutive sample of patients. SETTING: Acute brain injury rehabilitation unit in a large academic medical center. PATIENTS: Eleven acutely brain-injured adults were included by performing below two standard deviations of the age equivalent norms on 4 of 5 neuropsychological tests for attentional capacity. One subject was withdrawn after developing tachycardia. INTERVENTION: After a 1-week baseline assessment, subjects were placed on increasing doses of methylphenidate (Ritalin) so that on Day 7 all patients received a dose of 15 mg at 8 am and 12 pm. MAIN OUTCOME MEASURES: Nine neuropsychological subtests measured attention on admission, at 1 week, while on methylphenidate, and 1 week after its discontinuation. Functional outcome was evaluated utilizing the Disability Rating Scale (DRS) at the same intervals. RESULTS: Digit Span, Mental Control, and Symbol Search scores improved significantly (p < .05) on methylphenidate (A-B) as compared with the pre-methylphenidate (A-A) period. This advantage remained when the drug was removed. The mean improvement in DRS scores on methylphenidate approached a significant difference (p < .06) from that change in the DRS scores between baseline 1 and 2. CONCLUSIONS: Use of methylphenidate in acutely brain-injured adults was well tolerated and demonstrated a significant improvement in attention compared to natural recovery in a rehabilitation setting. Methylphenidate also correlated with faster functional recovery as measured by the Disability Rating Scale although the improvement did not achieve statistical significance.

Adult↗
PubMed2001

Effects of lithium chloride on induction and expression of methylphenidate sensitization.

Repeated administration of psychomotor stimulants produces an enduring and progressively enhanced behavioral response known as behavioral sensitization, which has been implicated as a model for psychiatric disorders such as mania, schizophrenia, and drug addiction. The objective of the study was to determine whether lithium chloride (LiCl), an anti-manic agent, is effective in blocking the development and/or the expression of behavioral sensitization to methylphenidate. Male Sprague-Dawley rats (n=64) weighing 170-190 g were randomly divided into seven treatment groups. A computerized animal activity monitor system continuously recorded locomotor activity for 16 days. Effects of LiCl on induction of methylphenidate sensitization were studied by giving LiCl before or during six daily methylphenidate administrations. Effects of LiCl on the expression of methylphenidate sensitization were studied by injecting LiCl after sensitization to methylphenidate was induced. It was shown that LiCl treatment modulated the acute methylphenidate effects by transiently attenuating the locomotor response to methylphenidate during the six daily methylphenidate administrations but neither single nor multiple treatments with LiCl blocked the development or the expression of behavioral sensitization.

Animals↗
PubMed2004

Efficacy and safety of methylphenidate in 45 adults with attention-deficit/hyperactivity disorder. A randomized placebo-controlled double-blind cross-over trial.

BACKGROUND: Data on the efficacy and safety of methylphenidate in adults with attention deficit/ hyperactivity disorder (ADHD) are lacking in Europe. This study was undertaken to report on the efficacy and safety of methylphenidate in an adult out-patient population with ADHD, and to compare results with US data. METHOD: A double-blind randomized cross-over trial comparing methylphenidate and placebo in 45 adults with ADHD with childhood onset was performed in a dose-titration design. Methylphenidate was titrated from 0.5 mg/kg per day in week 1 up to 1.0 mg/kg per day in week 3. RESULTS: Response rates using methylphenidate varied between 38 and 51%, and using placebo between 7 and 18% (p<0.05), depending on outcome measure used. Although the overall percentage of subjects having any side effect on both methylphenidate and placebo was rather high, side effects on methylphenidate over and above those on placebo were few and mild. CONCLUSIONS: Methylphenidate proves to be an effective and well tolerated treatment for symptoms of ADHD in adults in the short term. Future research should study the long-term response and clarify the impact of gender, co-morbidity, socio-economic status and IQ on response rates in adults with ADHD.

Adult↗
PubMed2006

Discriminative-stimulus, self-reported, performance, and cardiovascular effects of atomoxetine in methylphenidate-trained humans.

Atomoxetine is marketed as a nonstimulant medication indicated for the treatment of attention-deficit/hyperactivity disorder in adults. Previous laboratory research suggests that atomoxetine has limited abuse potential but that some of its behavioral effects might overlap with traditional psychomotor stimulants like methylphenidate and d-amphetamine. A drug with this profile might be useful for the treatment of stimulant dependence. The aim of this experiment was to compare the discriminative-stimulus and self-reported effects of atomoxetine with methylphenidate, damphetamine, and triazolam in humans who had acquired a methylphenidate (30 mg) discrimination. Six healthy subjects with a recent history of nontherapeutic stimulant use were enrolled in this outpatient study. After subjects acquired the methylphenidate discrimination, a range of doses of methylphenidate (5-30 mg), atomoxetine (15-90 mg), d-amphetamine (2.5-15 mg), triazolam (0.06-0.375 mg), and placebo were tested. To more fully characterize the behavioral effects of atomoxetine, a battery of self-reported drug-effect questionnaires, a performance task, and cardiovascular assessments were also included. Methylphenidate and d-amphetamine increased drug-appropriate responding and produced typical stimulant-like effects (e.g., increased ratings of "Active, Alert, Energetic"). Atomoxetine partially substituted for methylphenidate (i.e., 33%-50%) and produced some dose-dependent, stimulant-like, subject-rated drug effects, although the magnitude of these effects was less than d-amphetamine and methylphenidate and generally did not attain statistical significance. These data suggest that the behavioral effects of atomoxetine overlap to a small degree with psychomotor stimulants and that it has low abuse potential.

Adolescent↗
PubMed1999

Enantioselective gas chromatography-negative ion chemical ionization mass spectrometry for methylphenidate in human plasma.

Therapeutic doses of Ritalin, a racemic mixture of d- and l-threo-methyphenidate, result in low plasma concentrations of methylphenidate. In order to assess the safety and efficacy of methylphenidate, a sensitive analytical method is needed. A gas chromatography-negative ion chemical ionization mass spectrometry (GC-NCI-MS) assay capable of measuring both d- and l-enantiomers in human plasma was developed and validated to support clinical studies involving administration of d,l-methylphenidate. d,l-Methylphenidate-d3 is added to 1-mL plasma samples. The plasma samples are made basic, mixed with isopropanol and extracted with hexane. The hexane extracts are then back-extracted into 0.1 N HCl. The acidified aqueous extract is made basic, cooled to ice temperature, and the methylphenidate derivatized with heptafluorobutyryl-l-prolyl chloride. The two diastereomeric derivatives are then extracted into hexane. The hexane extract is evaporated to dryness, reconstituted in ethyl acetate, and analyzed by GC-NCI-MS. This method can accurately (+/- 5% target) and precisely (< 11.1% coefficient of variation) quantitate enantiomers of threo-methylphenidate in human plasma and in the whole blood at concentrations ranging from 0.75 to 100 ng/mL. Plasma samples are stable for up to five freeze-thaw cycles when the duration of each cycle did not exceed 0.5 h. The drug degraded gradually when plasma samples were left at room temperature; a 6% loss at 3 h progressed to 17% at 12 h and to 35% at 24 h. Therefore, it is important that extraction of plasma samples begins within 0.5 h after samples are removed from the freezer. Whole blood stability results show that concentrations of methylphenidate in whole blood, with or without NaF, stored for up to 6 h at room temperature did not deviate from the target concentration by more than 13%. The derivatized methylphenidate in extract is stable at 4 degrees C for up to 10 days.

Blood Chemical Analysis↗
PubMed2000

A double-blind, placebo-controlled study of Adderall and methylphenidate in the treatment of attention-deficit/hyperactivity disorder.

OBJECTIVE: While Adderall has been available for the treatment of attention-deficit/hyperactivity disorder (ADHD) for several years, there are few controlled studies comparing it to methylphenidate. METHOD: Fifty-eight children with ADHD (mean age 8.1 +/- 1.4 years) were randomly assigned to receive placebo, methylphenidate, or Adderall in a double-blind, parallel-group design for 3 weeks. Dosage was adjusted at the end of weeks 1 and 2 via an algorithm based on teacher and parent ratings. Final doses were 12.5 +/- 4.1 mg/day for Adderall and 25.2 +/- 13.1 mg/day for methylphenidate. Teacher and parent ratings, as well as the psychiatrist's Clinical Global Impression (CGI), were the final outcome measures at the end of week 3. RESULTS: Both medications were superior to placebo at reducing inattentive and oppositional symptoms in the classroom and on the CGI. Adderall produced significantly more improvements on teacher ratings and the CGI than methylphenidate, although the algorithm may have limited dosing in the methylphenidate group. Seventy percent of children in the Adderall group were given medication once a day, compared with 15% of the subjects receiving methylphenidate. CONCLUSIONS: Adderall compared favorably to methylphenidate, and the behavioral effects of Adderall appear to persist longer than those of methylphenidate after individual doses.

Algorithms↗
PubMed2000

Laboratory measures of methylphenidate effects in cocaine-dependent patients receiving treatment.

Two experiments examined the effects of methylphenidate in male and female patients enrolled in an outpatient treatment program for primary cocaine dependence. The first study was a component of a double-blind efficacy trial wherein 57 patients were first tested in a human laboratory for their initial responsiveness to medication. Patients were randomly assigned to receive either placebo or methylphenidate treatment and received their first dose in the human laboratory environment before continuing in outpatient treatment. Methylphenidate was given as a 20-mg sustained-release dose (twice daily) plus an additional 5-mg immediate-release dose combined with the morning dose. Methylphenidate increased heart rate and subjective ratings; however, the subjective effects were primarily of a "dysphoric" nature, and significant effects were limited to increases in anxiety, depression, and anger on the Profile of Mood States; shaky/jittery ratings on a visual analog scale; and dysphoria on the lysergic acid diethylamide (LSD) scale of the Addiction Research Center Inventory. Methylphenidate did not increase cocaine craving nor ratings suggesting abuse potential (i.e., Morphine-Benzedrine Group or drug-liking scores, etc.). None of the drug effects observed in the human laboratory was of clinical concern, and no subject was precluded from continuing in the outpatient study. After outpatient treatment completion, 12 patients were brought back into a second double-blind human laboratory study in which three doses (15, 30, and 60 mg) of immediate-release methylphenidate were administered in an ascending series preceded and followed by placebo. Methylphenidate produced dose-related increases in heart rate, subjective ratings of shaky/jittery, and LSD/dysphoria without significantly altering cocaine craving or stimulant euphoria ratings. These results suggest that stimulant substitution-type approaches to the treatment of cocaine dependence are not necessarily contraindicated because of cardiovascular toxicity or medication abuse potential. However, they also suggest that the subjective effects of methylphenidate may not be positive enough for an adequate replacement approach.

Adult↗