Navigation Links
Mouse Study Suggests ADHD Drug Might Be Addictive

But expert says finding doesn't apply to patients because doses used were so high

TUESDAY, Feb. 3 (HealthDay News) -- Ritalin, a drug commonly used to treat children with attention-deficit hyperactivity disorder (ADHD), caused changes in the brain cells of mice similar to those seen with cocaine, a new study shows.

The researchers, from The Rockefeller University in New York City, said the findings suggest that chronic exposure to Ritalin in high doses could prove addictive, and highlight the need for more research into its long-term effects.

However, one ADHD expert said he doubted the findings were applicable to children with the condition because the doses used in the study were so high.

Indeed, in experiments with mice, the researchers found that Ritalin in doses higher than those prescribed to treat ADHD caused changes in the reward region of the brain in a way comparable to cocaine. Ritalin and cocaine are both psycho-stimulants, the researchers noted.

"Methylphenidate [Ritalin] and cocaine have similar chemical structures and their pharmacological effects appear to be similar," said study author Yong Kim, a senior research associate at The Rockefeller University.

The findings were published in this week's online issue of the Proceedings of the National Academy of Sciences.

In their experiments, Kim and his colleagues compared the effects of chronic exposure to Ritalin and cocaine in specific reward-related brain regions of mice.

Over two weeks, mice were given daily injections of Ritalin or cocaine. The researchers looked for changes in dendritic spine formation, which is related to the formation of synapses and communication between nerve cells. They also looked for levels of a protein, delta Fos B, which is associated with long-term actions of addictive drugs.

"The results indicate that chronic exposure of methylphenidate, like cocaine, changes neuronal morphology and brain chemistry, but the precise pattern observed is distinct from that of cocaine," Kim said.

The changes in brain chemistry are known to be associated with the process of drug addiction, Kim added.

"Our results show addictive properties of methylphenidate, and imply that chronic exposure of methylphenidate in humans may lead to addiction," he said.

Kim noted that the researchers used higher doses of Ritalin than those prescribed to people. Also, taking the drug orally may not lead to addiction. But, if it's taken in high doses or injected, Ritalin could become addictive, he said.

"Indeed, methylphenidate is widely abused for improving concentration and enhancing performance, or for recreational purposes," Kim said.

But Dr. Jon A. Shaw, director of child and adolescent psychiatry at the University of Miami School of Medicine, thinks there's a greater risk of later substance abuse among children with ADHD who aren't treated with Ritalin.

"There is a lot of evidence that the use of Ritalin decreases the risk of substance abuse and cocaine use in adult life," Shaw said. "Untreated ADHD subjects are at higher risk for substance abuse and misuse of drugs in adulthood than treated ADHD [subjects]," he noted.

Shaw also noted that the mice in the study were given high doses of Ritalin. "Generalizing these findings to adults makes no sense," he said.

Shaw said he has seen only two cases of addiction to Ritalin. In both, the patients were taking higher-than-normal doses and taking them more often than prescribed.

A study published in March 2008 in the American Journal of Psychiatry found that children who are prescribed psycho-stimulants for ADHD are no more likely than their peers to abuse drugs and alcohol as young adults.

More information

For more on Ritalin, visit the U.S. National Library of Medicine.

SOURCES: Yong Kim, Ph.D., senior research associate, The Rockefeller University, New York City; Jon A. Shaw, M.D., professor and director, child and adolescent psychiatry, University of Miami School of Medicine; Feb. 2-6, 2009, Proceedings of the National Academy of Sciences

Copyright©2009 ScoutNews,LLC.
All rights reserved

Related medicine news :

1. Living with females extends the reproductive life of the male mouse, says Penn veterinary researcher
2. Cosmetic Surgery -Goldilocks Anesthesia Is Not Mickey Mouse
3. Common anesthetic induces Alzheimers-associated changes in mouse brains
4. Mouse model highlights histone methylation as distinguishing feature for leukemia subtypes
5. Mutant Mouse Gene Offers Clues to Hearing Loss
6. Mouse Study Finds Molecule That Tells Hair to Grow
7. Tumor suppressor genes speed up and slow down aging in engineered mouse
8. Mouse Skin Cells Reprogrammed to Act Like Embryonic Stem Cells
9. Mouse Adult Stem Cells Developed into Heart and Blood Cells
10. Mature Mouse Cells Reprogrammed to Stem Cell-Like State
11. Boston College biologists build a better mouse model for cancer research
Post Your Comments:
(Date:11/30/2015)... ... November 30, 2015 , ... TransPack Volume 6 features 30 customizable transitions ... scrolling web-styled transitions to wipes with blur & drop shadow options. Utilize the ... transition from one clip to the next with TransPack's easily customizable styles. ...
(Date:11/30/2015)... ... November 30, 2015 , ... Innovaacom, a leading ... results of a survey of educational needs for pharmacists worldwide. The poll of ... demand for high quality online and face-to-face education for pharmacists who are fast ...
(Date:11/30/2015)... ... November 30, 2015 , ... ... partnership at the Radiological Society of North America (RSNA) 2015 conference. , ... cutting-edge dictation and speech-enabled documentation software, announced their partnership today at RSNA ...
(Date:11/30/2015)... , ... November 30, 2015 , ... ... 2016. In 2016, expected coding changes are likely to include new codes for ... It’s not easy to understand the effects of code changes in musculoskeletal, radiology ...
(Date:11/30/2015)... ... ... announced the introduction of three Nightstick® brand LED traffic wands with an average retail price ... ), yellow ( NSP-1634 ) and blue ( NSP-1636 ), the SL-1600 series LED traffic ... blinking strobe mode using a fresh set of 3 AAA cells (included). , Built to ...
Breaking Medicine News(10 mins):
(Date:11/30/2015)... Royal Philips (NYSE: PHG AEX: PHIA) ... user interface and automatic scan parameter selection to help ... such as knee and hip replacements, spine implants and ... America Annual Meeting (RSNA) . The new software helps ... growing patient population. ScanWise Implant adds to Philips, suite ...
(Date:11/30/2015)... and BOCA RATON, Fla. , Nov. ... Commercialization of Public Research (the Institute) announced today ... KynderMed , a medical device start-up company with technology ... company creation based on publicly-funded research, and bridges early ... Florida -based universities and research institutions. ...
(Date:11/30/2015)... , Nov. 30, 2015 ... global biopharmaceutical leader dedicated to delivering transformative ... underserved medical conditions, today announced the launch ... (Recombinant), PEGylated], an extended circulating half-life recombinant ... based on full-length ADVATE [Antihemophilic Factor (Recombinant)]. ...
Breaking Medicine Technology: