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Friday, July 24, 2009

ADHD Drugs are a paradox

According to a new article written by Edmund S. Higgins at the Scientific America web site, ,

"With the expanded and extended use of stimulants comes mounting concern that the drugs might take a toll on the brain over the long run. Indeed, a smattering of recent studies, most of them involving animals, hint that stimulants could alter the structure and function of the brain in ways that may depress mood, boost anxiety and, contrary to their short-term effects, lead to cognitive deficits. Human studies already indicate the medications can adversely affect areas of the brain that govern growth in children, and some researchers worry that additional harms have yet to be unearthed."

Higgins goes on to state: "the vast majority of adults with ADHD experience at least one additional psychiatric illness—often an anxiety disorder or drug addiction—in their lifetime." <:(

Key aspects discussed in this article include:

"And at least three studies using animals hint that exposure to methylphenidate during childhood may alter mood in the long run, perhaps raising the risk of depression and anxiety in adulthood". Methylphenidate (also known as Ritalin), is the most commonly prescribed "psychostimulant".

"In January 2009 child psychiatrist Philip Shaw of the National Institute of Mental Health and his colleagues used MRI scans to measure the change in the thickness of the cerebral cortex (the outer covering of the brain) of 43 youths between the ages of 12 and 16 who had ADHD. The researchers found no evidence that stimulants slowed cortical growth. In fact, only the unmedicated adolescents showed more thinning of the cerebrum than was typical for their age, hinting that the drugs might facilitate normal cortical development in kids with ADHD."

"The long-term use of any drug that affects the brain’s reward circuitry also raises the specter of addiction. Methyl-phenidate has a chemical structure similar to that of cocaine and acts on the brain in a very similar way. Both cocaine and methamphetamine (also called “speed” or “meth”)—another highly addictive stimulant—block dopamine transporters just as ADHD drugs do."

"Furthermore, the scientists found that methylphenidate boosted the amount of a protein called ΔFosB, which turns genes on and off, even more than cocaine did. That result could be a chemical warning of future problems: excess ΔFosB heightens an animal’s sensitivity to the rewarding effects of cocaine and makes the animal more likely to ingest the drug. Many former cocaine addicts struggle with depression, anxiety and cognitive problems. Researchers have found that cocaine has remodeled the brains of such ex-users. Similar problems—principally, perhaps, difficulty experiencing joy and excitement in life—could occur after many years of Ritalin or Adderall use."

"The evidence to date, including two 2008 studies from the National Institute on Drug Abuse, indicates that children treated with stimulants early in life are not more likely than other children to become addicted to drugs as adults. In fact, the risk for severe cases of ADHD may run in the opposite direction."

"Amphetamines such as Adderall could alter the mind in other ways. A team led by psychologist Stacy A. Castner of the Yale University School of Medicine has documented long-lasting behavioral oddities, such as hallucinations, and cognitive impairment in rhesus monkeys that received escalating injected doses of amphetamine over either six or 12 weeks."

"A report published in 2005 by neurologist George A. Ricaurte and his team at the Johns Hopkins University School of Medicine is even more damning to ADHD meds because the researchers used realistic doses and drug delivery by mouth instead of by injection. Ricaurte’s group trained baboons and squirrel monkeys to self-administer an oral formulation of amphetamine similar to Adderall: the animals drank an amphetamine-laced orange cocktail twice a day for four weeks, mimicking the dosing schedule in humans. Two to four weeks later the researchers detected evidence of amphetamine-induced brain damage, encountering lower levels of dopamine and fewer dopamine transporters on nerve endings in the striatum—a trio of brain regions that includes the nucleus accumbens—in amphetamine-treated primates than in untreated animals. The authors believe these observations reflect a drug-related loss of dopamine-releasing nerve fibers that reach the striatum from the brain stem."
Stimulants do seem to stunt growth in children. Otherwise, however, studies in humans have largely failed to demonstrate any clear indications of harm from taking ADHD medications as prescribed. Whether the drugs alter the human brain in the same way they alter that of certain animals is unknown, because so far little clinical data exist on their long-term neurological effects."

"So far the best-documented problem associated with the stimulants used to treat attention-deficit hyperactivity disorder (ADHD) concerns growth. Human growth is controlled at least in part through the hypothalamus and pituitary at the base of the brain. Studies in mice hint that stimulants may increase levels of the neurotransmitter dopamine in the hypothalamus as well as in the striatum (a three-part brain structure that includes part of its reward circuitry) and that the excess dopamine may reach the pituitary by way of the bloodstream and act to retard growth."

"Recent work strongly indicates that the drugs can stunt growth in children. In a 2007 analysis of a National Institute of Mental Health study of ADHD treatments involving 579 children, research psychiatrist Nora Volkow, who directs the National Institute of Drug Abuse, and her colleagues compared growth rates of unmedicated seven- to 10-year-olds over three years with those of kids who took stimulants throughout that period. Relative to the unmedicated youths, the drug-treated youths showed a decrease in growth rate, gaining, on average, two fewer centimeters in height and 2.7 kilograms less in weight. Although this growth-stunting effect came to a halt by the third year, the kids on the meds never caught up to their counterparts."

Edmund S. Higgins is clinical associate professor of family medicine and psychiatry at the Medical University of South Carolina and co-author, with Mark S. George, of The Neuroscience of Clinical Psychiatry (Lippincott Williams & Wilkins, 2007) and Brain Stimulation Therapies for Clinicians (American Psychiatric Publishing, 2009).

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Thoughts worth thinking about

"Our subconscious minds have no sense of humor, play no jokes and cannot tell the difference between reality and an imagined thought or image. What we continually think about eventually will manifest in our lives."-Sidney Madwed

Laws alone can not secure freedom of expression; in order that every woman and man present their views without penalty, there must be spirit of tolerance in the entire population.- Albert Einstein Too often we underestimate the power of a touch, a smile, a kind word, a listening ear, an honest compliment, or the smallest act of caring, all of which have the potential to turn a life around. - Leo Buscaglia

A person's true wealth is the good he or she does in the world. - Mohammed

Our task must be to free ourselves... by widening our circle of compassion to embrace all living creatures and the whole of nature and its beauty. -Albert Einstein

The best way to find yourself, is to lose yourself in the service of others. - Ghandi

The unselfish effort to bring cheer to others will be the beginning of a happier life for ourselves. - Helen Keller

Aim for success, not perfection. Never give up your right to be wrong, because then you will lose the ability to learn new things and move forward with your life. Remember that fear always lurks behind perfectionism. Confronting your fears and allowing yourself the right to be human can, paradoxically, make yourself a happier and more productive person. - Dr. David M. Burns

Life is as dear to a mute creature as it is to man. Just as one wants happiness and fears pain, just as one wants to live and not die, so do other creatures. -His Holiness The Dalai Lama

Mankind's true moral test, its fundamental test (which lies deeply buried from view), consists of its attitude towards those who are at its mercy: animals. And in this respect mankind has suffered a fundamental debacle, a debacle so fundamental that all others stem from it. -

Milan Kundera, The Unbearable Lightness of Being

The worst sin towards our fellow creatures is not to hate them, but to be indifferent to them. That's the essence of inhumanity. -George Bernard Shaw

Ego's trick is to make us lose sight of our interdependence. That kind of ego-thought gives us a perfect justification to look out only for ourselves. But that is far from the truth. In reality we all depend on each other and we have to help each other. The husband has to help his wife, the wife has to help the husband, the mother has to help her children, and the children are supposed to help the parents too, whether they want to or not.-Gehlek Rinpoche Source: "The Best Buddhist Writing 2005 pg. 165

The hostile attitude of conquering nature ignores the basic interdependence of all things and events---that the world beyond the skin is actually an extension of our own bodies---and will end in destroying the very environment from which we emerge and upon which our whole life depends.