Showing posts sorted by date for query Ritalin. Sort by relevance Show all posts
Showing posts sorted by date for query Ritalin. Sort by relevance Show all posts

Wednesday, February 27, 2019

Animal Study Suggests Ritalin Won't Harm the Heart


    Methylphenidate-2D-skeletal.svg

In continuation of my update on Ritalin 

Ritalin, a widely used stimulant drug to treat attention-deficit/hyperactivity disorder (ADHD), likely poses no risk of heart damage in children, new research in monkeys suggests.
The findings are "very reassuring," said the study's principal investigator, Dr. Steven Lipshultz.
Each year, more than 1.8 million children in the United States take drugs to treat ADHD. Concerns have been raised that Ritalin, Concerta and other forms of methylphenidate could harm children's hearts.
Some studies have reported an increase in sudden cardiac death among children taking methylphenidate or other stimulant drugs for ADHD.
But this new study found that five years of high doses of methylphenidate did not damage the hearts of 30 rhesus monkeys. That length of time is similar to how long children and adults would use the drugs.
"Even high-dose chronic [methylphenidate] stimulant therapy did not result in any evidence of abnormal structures or function in the hearts of the monkeys," said Lipshultz, chair of pediatrics at the University at Buffalo School of Medicine and Biomedical Sciences, in New York.
However, his team cautioned that the results of animal research are not automatically applicable to humans.
One ADHD specialist unconnected to the study agreed.
"The [animal] study cannot be automatically applicable to humans," said Dr. Victor Fornari, who directs child and adolescent psychiatry at Zucker Hillside Hospital in Glen Oaks, N.Y.
Still, the findings "provide compelling evidence of the cardiac safety of this important evidence-based treatment for ADHD," Fornari said.
About 10 percent of U.S. children have been diagnosed with ADHD and related disorders. Up to 70 percent of them take prescription stimulant drugs, so possible heart risks associated with the drugs are a major concern, study author Lipshultz said in a university news release.
The U.S. Food and Drug Administration has ordered some prescription stimulants to carry black box warnings stating that children with underlying heart disease should use these medications with caution.
In Canada, a stimulant drug was removed from the market after it was linked to a small number of sudden cardiac deaths. Sales of the drug later resumed.
"This controversy has persisted without answer," Lipshultz said. "Yet the number of prescriptions for these medications for children with ADHD continues to expand."
Another expert said the new findings should help ease concerns.
The study results "are overall re-assuring in terms of cardiac safety and long-term use of stimulants for ADHD in otherwise healthy individuals," said Dr. Andrew Adesman, chief of developmental and behavioral pediatrics at Cohen Children's Medical Center in New Hyde Park, N.Y.
However, he added that the study "does not address clinical concerns about the safety of stimulants in individuals with certain types of heart disease."
Therefore, "health care providers need to continue to screen children for cardiac problems prior to prescribing stimulant medications like Ritalin, Concerta or Adderall, since there are some individuals who may still be at increased risk for potentially serious heart problems if treated with stimulant medication," Adesman said.
Lipshultz noted that the findings are good news for another type of pediatric patient: young cancer survivors.
"I have cared for children and adolescents who have survived childhood cancer, who now are experiencing severe learning disabilities as a result of their cancer therapies. They become my patients because their hearts have been damaged, an unfortunate effect of the successful treatment of their childhood cancer," he said.
"Current recommendations state that children such as these, with underlying heart disease, should avoid chronic stimulant therapy because of the concern that it could further damage their hearts," he explained. "However, these prescription stimulants often allow these children to do much better with their learning progress."
The new findings suggest that, in many cases, these medications can be prescribed to these children as well, Lipshultz said.

Thursday, September 9, 2010

Methylphenidate facilitates recovery from drug addiction...



A brain-scanning study at the U.S. Department of Energy's (DOE) Brookhaven National Laboratory, conducted with collaborators from Stony Brook University, reveals that an oral dose of methylphenidate, commonly known as Ritalin, improves impaired brain function and enhances cognitive performance in people who are addicted to cocaine.

Researchers were encouraged by the fact that, methylphenidate does decrease behaviors such as risk taking and impulsivity and improves brain function and cognitive performance in a range of other conditions that also affect the brain's prefrontal cortex, including attention deficit hyperactivity disorder (ADHD), some forms of dementia, and certain kinds of brain injury. To begin with Goldstein's (lead researcher)  group performed functional magnetic resonance imaging (fMRI) on 13 cocaine users and 14 healthy control subjects who were asked to perform a cognitive task after being given either a low oral dose of methylphenidate (20 milligrams) or a placebo. The task involved pushing a button to correctly identify the color of a printed word; some words had to do with drug use, others were "neutral." Subjects received monetary rewards for correct answers. The scientists were particularly interested in two parts of the prefrontal cortex previously shown to be impaired during this cognitive activity in cocaine-addicted individuals.

"These regions help to regulate emotion, cognition, and behavior in response to salient stimuli - the things we find particularly interesting or relevant," Goldstein said. "Because drug users have deficits in these regions, they may have less ability to regulate their emotions and exert cognitive control over certain behaviors."

Researchers found that,  compared  with cocaine users given placebos - who (compared to healthy controls) exhibited reduced function in these prefrontal cortex regions - cocaine users given a low dose of methylphenidate had improved brain function such that they were more like the healthy control subjects. The subjects given methylphenidate were also less likely to make "errors of commission" (pressing a button incorrectly or prematurely), a measure of impulsivity, while performing the cognitive task than subjects given a placebo. Furthermore, the greater the improvement in task accuracy with methylphenidate, the larger the increase in fMRI signal in the prefrontal cortex regions of interest, showing that the improvements in brain function were directly related to improved cognitive performance.

Though future studies need to evaluate whether these results can be generalized to other tasks or activities that involve these specific brain regions, but these results do suggest that by enhancing prefrontal cortex function and associated cognitive performance - particularly the decrease in impulsivity - methylphenidate could help to improve clinical outcomes in people seeking to overcome drug addiction…
  
 Ref : http://www.pnas.org/content/early/2010/08/30/1011455107.full.pdf+html?sid=be34425f-b8cc-4a90-8929-03aca9f8bbe4