Duke Study Faults Overuse of Stimulants for Children

Marshall, Eliot

doi:10.1126/science.289.5480.721

Cited by 14 publications

(6 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Estimates show that up to 15% of school age children may be affected in certain geographical locations (Scahill and Schwab-Stone 2000) and that prevalence is estimated to be 5-10% in the general population (Swanson et al 1998). In addition, preschoolers (Zito et al 2000) and children who do not meet the diagnostic criteria for ADHD (Marshall 2000) have recently been identified as two new groups increasingly exposed to this drug. The duration of treatment is several years in childhood, more often extending into adolescence and adulthood (Garland 1998;Robin 1999;Silver 2000;Spencer et al 2000).…”

Section: Treatment Of Attention Deficit Hyperactivity Disorder With Tmentioning

confidence: 99%

Enhanced Reactivity and Vulnerability to Cocaine Following Methylphenidate Treatment in Adolescent Rats

Brandon

Marinelli²,

Baker

et al. 2001

Neuropsychopharmacology

225

147

View full text Add to dashboard Cite

Treatment of attention deficit hyperactivity disorder with the psychostimulant drug methylphenidate (MP) has increased dramatically among schoolchildren. We tested whether repeated exposure to moderate doses of MP (5 and 10 mg/kg IP for 5 or 7 days) in adolescent rats increased reactivity to cocaine measured by motor responses (ambulations and rearing) to a cocaine challenge in adulthood. We later tested whether repeated exposure to a low dose of MP (2 mg/kg IP for 7 days) enhanced the psychomotor effects of cocaine, measured by different challenge doses (0-30 mg/kg) as well as to the reinforcing effects of cocaine, measured by self-administration of lowdose infusion (75 g/kg, IV). We found that exposure to moderate doses of MP enhanced psychomotor responses to cocaine but exposure to a low dose only increased cocaine self-administration. These results suggest that adolescent exposure to low doses of MP in rats mayMethylphenidate (Ritalin ® ) is used widely in the treatment of attention deficit hyperactivity disorder (ADHD), the most commonly diagnosed disorder of childhood (Swanson et al. 1998). During the 1990s, diagnosis and treatment of this disorder grew dramatically in the United States. Estimates show that up to 15% of school age children may be affected in certain geographical locations (Scahill and Schwab-Stone 2000) and that prevalence is estimated to be 5-10% in the general population (Swanson et al. 1998). In addition, preschoolers (Zito et al. 2000) and children who do not meet the diagnostic criteria for ADHD (Marshall 2000) have recently been identified as two new groups increasingly exposed to this drug. The duration of treatment is several years in childhood, more often extending into adolescence and adulthood (Garland 1998;Robin 1999;Silver 2000;Spencer et al. 2000).Animal studies have shown that MP is a psychostimulant, which, as with cocaine, blocks the dopamine transporter (DAT) (Kuczenski and Segal 1997); thereby increasing extracellular dopamine (DA) levels in the striatum and nucleus accumbens (Kuczenski 1983), brain regions involved in the locomotor and reinforcing effects of psychostimulants and other drugs of abuse (Koob and Bloom 1988 NO . 5 et al. 1999). Oral therapeutic doses of MP effectively block more than 50% of DATs (Volkow et al. 1998); thereby increasing extracellular DA levels (Volkow et al. 2001). These actions are highly associated with the reinforcing properties of drugs (Ritz et al. 1987). Taken together, the well-documented abuse potential of psychostimulants (for reviews see White and Wolf 1991;Robinson and Berridge 1993;Self and Nestler 1995), studies linking ADHD with subsequent substance abuse (Wilens et al. 1997;Clure et al. 1999;Schubiner et al. 2000), and the dearth of controlled studies on the effects of long-term stimulant exposure on the brain, all make MP exposure an important public health issue.Animal models of drug addiction clearly indicate that repeated exposure to psychostimulants results in augmented behaviors (sensitization) that can be detected lo...

show abstract

Section: Treatment Of Attention Deficit Hyperactivity Disorder With Tmentioning

confidence: 99%

Enhanced Reactivity and Vulnerability to Cocaine Following Methylphenidate Treatment in Adolescent Rats

Brandon

Marinelli²,

Baker

et al. 2001

Neuropsychopharmacology

225

147

View full text Add to dashboard Cite

show abstract

“…Attention deficit/hyperactivity disorder (ADHD) affects 2-18% of children in the United States, with higher prevalence among boys (Silver, 1999;Marshall, 2000;Hechtman, 2006). ADHD is characterized by developmentally inappropriate symptoms of impulsivity, inattentiveness, and overactivity (Sagvolden and Sergeant, 1998).…”

Section: Introductionmentioning

confidence: 99%

Methylphenidate Administration to Juvenile Rats Alters Brain Areas Involved in Cognition, Motivated Behaviors, Appetite, and Stress

Gray

Punsoni²,

Tabori³

et al. 2007

J. Neurosci.

105

View full text Add to dashboard Cite

Thousands of children receive methylphenidate (MPH; Ritalin) for attention deficit/hyperactivity disorder (ADHD), yet the long-term neurochemical consequences of MPH treatment are unknown. To mimic clinical Ritalin treatment in children, male rats were injected with MPH (5 mg/kg) or vehicle twice daily from postnatal day 7 (PND7)-PND35. At the end of administration (PND35) or in adulthood (PND135), brain sections from littermate pairs were immunocytochemically labeled for neurotransmitters and cytological markers in 16 regions implicated in MPH effects and/or ADHD etiology. At PND35, the medial prefrontal cortex (mPFC) of rats given MPH showed 55% greater immunoreactivity (-ir) for the catecholamine marker tyrosine hydroxylase (TH), 60% more Nissl-stained cells, and 40% less norepinephrine transporter (NET)-ir density. In hippocampal dentate gyrus, MPH-receiving rats showed a 51% decrease in NET-ir density and a 61% expanded distribution of the new-cell marker PSA-NCAM (polysialylated form of neural cell adhesion molecule). In medial striatum, TH-ir decreased by 21%, and in hypothalamus neuropeptide Y-ir increased by 10% in MPH-exposed rats. At PND135, MPH-exposed rats exhibited decreased anxiety in the elevated plus-maze and a trend for decreased TH-ir in the mPFC. Neither PND35 nor PND135 rats showed major structural differences with MPH exposure. These findings suggest that developmental exposure to high therapeutic doses of MPH has short-term effects on select neurotransmitters in brain regions involved in motivated behaviors, cognition, appetite, and stress. Although the observed neuroanatomical changes largely resolve with time, chronic modulation of young brains with MPH may exert effects on brain neurochemistry that modify some behaviors even in adulthood.

show abstract

“…They also claim that even if drugs are overprescribed, ADHD is under diagnosed. 122 Greenhill claims, "The percentage of U.S. youth being treated with psychostimulants is well within the estimates of the prevalence of ADHD." 123 Jensen asserts that "only about one-half the children with ADHD are getting treated."…”

Section: W22mentioning

confidence: 84%

Children in Clinical Research: A Conflict of Moral Values

Sharav¹

2003

The American Journal of Bioethics

View full text Add to dashboard Cite

This paper examines the culture, the dynamics and the financial underpinnings that determine how medical research is being conducted on children in the United States. Children have increasingly become the subject of experiments that offer them no potential direct benefit but expose them to risks of harm and pain. A wide range of such experiments will be examined, including a lethal heartburn drug test, the experimental insertion of a pacemaker, an invasive insulin infusion experiment, and a fenfluramine "violence prediction" experiment. Emphasis, however, is given to psychoactive drug tests because of the inherent ethical and diagnostic problems involved in the absence of any objective, verifiable diagnostic tool. Effort is made to provide readers comprehensive reference sources to evidence-based reports about the serious risks these drugs pose for adults and children so that the reader may judge whether the benefits (if any) outweigh the risks for children.

show abstract

Duke Study Faults Overuse of Stimulants for Children

Cited by 14 publications

References 0 publications

Enhanced Reactivity and Vulnerability to Cocaine Following Methylphenidate Treatment in Adolescent Rats

Enhanced Reactivity and Vulnerability to Cocaine Following Methylphenidate Treatment in Adolescent Rats

Methylphenidate Administration to Juvenile Rats Alters Brain Areas Involved in Cognition, Motivated Behaviors, Appetite, and Stress

Children in Clinical Research: A Conflict of Moral Values

Contact Info

Product

Resources

About