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Study drugs: How do they work?

BY KINGSON MAN
Daily Staff Reporter
Published April 18, 2005

For the 3 to 7 percent of students diagnosed with Attention Deficit Hyperactivity Disorder, stimulants like Ritalin or Adderall may mean the difference between success and failure in classes. The exact mechanism by which these drugs work, however, is still a puzzle for scientists. And, for students who abuse these prescription medications, the results are often unpredictable.

The popular prescription drug dextroamphetamine, sold under the names Adderall and Dexedrine, is a central nervous system stimulant. Its effects on different kinds of people, however, can be counterintuitive.

Despite being called stimulants, the class of drugs known as amphetamines actually has a calming effect on sufferers of ADHD. Children afflicted with the disorder “don’t have the capacity to concentrate, and trail and shift from one task to another,” said Maher Karam-Hage, an addiction psychiatrist and director of the Chelsea-Ann Arbor Treatment Center.

Sufferers with ADHD are believed to lack certain neurotransmitters — chemicals released by brain cells that influence the action of other brain cells — in the frontal lobes of their brains. This is the area of the brain closest to the forehead with the most advanced brain functions, responsible for coordinating our actions and planning our next moves while blocking out other impulses we may have. Without it, the ability to concentrate and block out impulsive actions is impaired.

“You want to think of the brain as several areas,” Karam-Hage said. “There are impulse-generating areas and impulse-controlling areas. With ADHD, the frontal lobe is not working to inhibit other areas of the brain.”

For narcoleptics, or people who fall asleep uncontrollably, amphetamines function the way other kinds of stimulants do — they promote wakefulness. For narcoleptics and healthy people, the stimulants can cause the brain to pump out much more of the neurotransmitter dopamine in the frontal lobes, keeping a person awake, alert and “wired.”

According to the National Institutes on Drug Abuse, common side effects to these drugs are the jitters, feelings of nervousness or paranoia, and anxiety — an experience akin to drinking too many cups of coffee.

Students who take Adderall or Dexedrine often report staying awake for extended periods of time. They also swear by the fact that the drugs impart a heightened focus and ability to concentrate.

But in his opinion, Karam-Hage said, “For the person (using these drugs) who doesn’t have ADHD, I think it is an illusion that they are concentrating more.”

In contrast, the consequences of these drugs are well documented. The areas of the brain that control pleasure and addiction are loaded with dopamine.

“With Ritalin and amphetamines, you run the risk of addiction if you’re not careful,” Karam-Hage said. The Drug Enforcement Agency has classified amphetamine-based stimulants under the Class II schedule, carrying restrictions on prescriptions and refills of the medication.

A 2005 report in the journal Addiction by Sean McCabe, acting director of the University Substance Abuse Research Center, surveyed illicit prescription stimulant use at four-year universities. At one college, up to 25 percent of respondents indicated that they had abused stimulants during the past year. It was also found that more competitive universities had higher rates of stimulant abuse.

The pharmaceutical community is moving toward alternate treatment options with drugs that control norepinephrine, another neurotransmitter found in the frontal lobe. Sold under the brand names Wellbutrin and Strattera, they are slower-acting and lack the dopamine kick of amphetamines. The epinephrine drugs are less likely to be abused, though they can take up to several weeks to show an effect.

Karam-Hage believed that the popular conception of using “study drugs” to enhance academic performance during the upcoming exam period was still misplaced. “It’s not even the ethics – it’s simply not effective,” the psychiatrist said. “So you’re shooting yourself, not in the foot, but in the head, right?”


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