Long-term ADHD drug use appears safe, brain development not affected

July 18, 2012, Wake Forest University Baptist Medical Center

Drugs used to treat Attention Deficit Hyperactivity Disorder (ADHD) do not appear to have long-term effects on the brain, according to new animal research from Wake Forest Baptist Medical Center.

As many as five to seven percent of elementary school children are diagnosed with ADHD, a behavioral disorder that causes problems with inattentiveness, over-activity, , or a combination of these traits. Many of these children are treated with psychostimulant drugs, and while doctors and scientists know a lot about how these drugs work and their effectiveness, little is known about their long-term effects.

Linda Porrino, Ph.D., professor and chair of the Department of Physiology and Pharmacology, along with fellow professor Michael A. Nader, Ph.D., both of Wake Forest Baptist, and colleagues conducted an to determine what the long-lasting effects may be. Their findings were surprising, said Porrino.

"We know that the drugs used to treat ADHD are very effective, but there have always been concerns about the long-lasting effects of these drugs," Porrino said. "We didn't know whether taking these drugs over a long period could harm in some way or possibly lead to abuse of drugs later in adolescence."

Findings from the Wake Forest Baptist research are published online this month in the journal Neuropsychopharmacology.

The researchers studied 16 juvenile non-human primates, whose ages were equivalent to 6-to 10-year-old humans. Eight animals were in the that did not receive any treatment and the other eight were treated with a therapeutic-level dose of an extended-release form of Ritalin, or (MPH), for over a year, which is equivalent to about four years in children. Imaging of the animals' brains, both before and after the study, was conducted on both groups to measure and structure. The researchers also looked at to address concerns that ADHD drugs adversely affect physical growth.

Once the MPH treatment and imaging studies were concluded, the animals were given the opportunity to self administer cocaine over several months. Nader measured their propensity to acquire the drug and looked at how rapidly and in what amounts, to provide an index of vulnerability to substance abuse in adolescence. As reported in the research paper, they found no differences between groups – monkeys treated with Ritalin during adolescence were not more vulnerable to later drug use than the control animals.

"After one year of drug therapy, we found no long-lasting effects on the neurochemistry of the brain, no changes in the structure of the developing brain. There was also no increase in the susceptibility for drug abuse later in adolescence," Porrino said. "We were very careful to give the drugs in the same doses that would be given to children. That's one of the great advantages of our study is that it's directly translatable to children."

Porrino said non-human primates provide exceptional models for developmental research because they undergo relatively long childhood and adolescent periods marked by hormonal and physiological maturation much like humans.

"Our study showed that long-term therapeutic use of drugs to treat ADHD does not cause long-term negative effects on the developing , and importantly, it doesn't put children at risk for substance abuse later in adolescence," she said.

One of the exciting things about this research, Porrino said, is that a "sister" study was conducted simultaneously at John Hopkins with slightly older aged animals and different drugs and their findings were similar. "We feel very confident of the results because we have replicated each other's studies within the same time frame and gotten similar results," she said. "We think that's pretty powerful and reassuring."

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not rated yet Jul 18, 2012
Of course, today, it doesn't make much sense to talk about the individual without also discussing their role in society. It's not as though we are all foraging for berries and nuts these days; we all rely upon cooperation between a complex system of people in order for society, as a whole, to succeed.

Seeing that ADHD has such a high prevalence, it's fair to wonder if it is actually a disorder at all (for society). Given the known correlations to creativity, one can also fairly wonder if the reason it persists in societies is due to a societal role, as a means of increasing the number of creative ideas which a society has access to.

In such a hypothetical scenario, a society which attempts to engineer this influence out can cause unfortunate side-effects for the future of that society, if it does not collectively realize that it should be compensating.

This isn't my idea. The case is made a bit more eloquently here:

5 / 5 (1) Jul 18, 2012
"monkeys treated with Ritalin during adolescence were not more vulnerable to later drug use than the control animals."

I have to wonder what the above statement really means. Perhaps all monkeys used as much cocaine as possible until they died, or maybe none of the monkeys used the cocaine.

Also, what does "given the opportunity to self administer cocaine" really mean?
5 / 5 (1) Jul 18, 2012
I found no quantitative statistics that convinced me that medication is the way to go. I feel that parents with children and persons suffering from ADHD/ADD should seek alternatives to the current medications available. I have a child with ADHD. I tried the Ritalin with little to no success. I found the drug made my child lethargic and once it wore off she would either crash or become even more hyper-active. Believe me, I tried it for a period of time to see if it would build up in her system and alleviate not only the behavior but the side effects. It did not. After doing much research I found a program that is working for my child and my family. I use Play Attention. Play Attention is a program that builds behavioral shaping. Since investing my child's mental health into this platform I have now learned that they are using this program at nuclear power plants, nascar mechanics use it, why? To focus and
5 / 5 (2) Jul 18, 2012
Were the monkeys diagnosed ADHD? Otherwise, how the study translate to ADHD diagnosed humans?
3 / 5 (2) Jul 18, 2012
Hi, i was diagnosed with Paranoid Schizophrenia at the age of 15 after taking Ritalin for ADHD for 3 years. The doctors told my parents that my condition could only be from Marijuana usage, yet i hadn't ever smoked Marijuana. My parents and doctor both agreed that i was using Marijuana, so they took me off Ritalin and gave me a prescription of some kind of anti-psychotic. I never took the anti-psychotic.

I've watched my son's behavior as he has grown over the years, he is just like me, hyper-active, poor concentration, defiant, straight A's in school. He is in his second year in primary school, his prep teacher told us he has Autism and referred us to a specialist, his year 1 teacher said he has Bipolar, and referred us to a specialist, his year 2 teacher diagnosed him ADHD, and referred us to a specialist, despite being the best reader in the class.

ADHD is not a disorder, but a set of personality traits, if you have a % of those traits, your ADHD,.. apparently

not rated yet Jul 23, 2012
"ADHD is not a disorder, but a set of personality traits, if you have a % of those traits, your ADHD,.. apparently"
Ya Wanna Bet?!There is proven neurotransmitter dysregulation.I think that that rules out the'personality traits'theory.&I am talking from first hand experience.I fell thru the cracks & only got an adult diagnosis.I was promptly put on a stimulant.The result:I LITERALLY went manic(shrink then tried to tell me that I now had bipolar, wasn't true),my sense of reality & time became very distorted & on a very low dose too.If you were diagnosed with PS, then the following might actually apply:you mayhave a form of ADHD that is not primarily dopamine driven(stimulants are the WORST thing you can take here), then the following might be illuminating.It refines on the 3subtype model.
There are non-stimulant ADHDmeds.The docs just don't appear to be keen to push them.CheersDH66
not rated yet Jul 23, 2012
I should also mention that I now take tyrosine to help with the stress & easy tiring that ADHD can bring on because of the hyperactivity &take other alternative medicines titrated to assist with the acetycholine neutrotransmitter, which is where MY deficit happens to be.The end result is not perfect, but it does bring some relief.It is also possible that ADHD & autism can coexist.I am also a very good reader & speller(my country does not spell in American, so don't judge by that), despite having a number of resulting learning disorders.Deficiencies in spelling & reading are a result of learning disorders(not ADHD itself) &these can also arise out of other conditions as separate & distinct symptoms(eg ADHD), as well as being standalones & there are many,many different types.Your son might just be lucky in that department.So that is not necessarily a valid yardstick.As for the the sites I gave you, they may not be the normal way that ADHD is subcategorised, but are more precise.DH66:)
5 / 5 (1) Jul 23, 2012
I agree with untur2k: Were the monkeys diagnosed ADHD? Otherwise, how the study translate to ADHD diagnosed humans? I do not understand the correlation between monkey and man in this study. So what if the neurochemistry did not change? Were there behavioral changes that would indicate that the drug was safe?

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