NEW HAVEN, Conn. – An increasing number of college students in the U.S. and elsewhere are taking prescription amphetamines as a “productivity drug,” but the benefits and long-term effects remain largely unknown.

The Sydney Morning Herald recently spoke with students at Yale University about an epidemic of Adderall and other prescription drug abuse on campus, and the school’s reluctance to crack down on the problem.

“When I’m under the gun and there’s a big assignment … it gets really unhealthy,” a student using the pseudonym Graham told the news site. “Every six hours I’m taking another 20mg. It’s brutal. Cognitively you feel f*****, the neurons aren’t really firing but you have no choice.”

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Graham said a doctor from his home town prescribed Adderall to help him concentrate, and he often goes for days with little or no sleep. He also needs sedatives to sleep sometimes after staying up too long on Adderall.

“I feel like I’m making a deal with the devil, where in exchange for short-term productivity and energy and focus now, I’m giving up the last five years of my life,” Graham told the Morning Herald. “I joke about this, but who knows what the long term effects are?”

The long-term effects of Adderall use on healthy people hasn’t been studied, but research shows Yale students aren’t the only ones abusing amphetamines to get ahead in school.

According to the Morning Herald:

In the two most respected academic studies, conducted by researchers at the University of Maryland and the University of Kentucky, 31 per cent and 34 per cent of the students surveyed admitted misusing prescription stimulants at least once. But that data is more than 5 years old, and the trend is upwards. Between 2007-2011, the number of monthly prescriptions issued to 20- to 29-year-olds reporting the symptoms of ADHD climbed from 5.6 million to 14 million.

Another Yale student using the pseudonym Lyndon told the news site he was diagnosed with ADHD when he was 6 years old and was prescribed Adderall, but it made him too wired. Now he takes Ritalin, but only when necessary to concentrate.

Instead of selling his extra pills, which can go for as much as $1 per milligram, he flushes them down the toilet at the end of his term.

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“I know people that can’t do basic assignments without having some kind of stimulant in their system, which is super alarming,” Lyndon told the Morning Herald.

Pills are sold every day through Yale’s “sprawling underground economy,” Lyndon said, but the Morning Herald reports “a search of Yale’s public records reveals that no student has ever been disciplined for non-medical use of prescription stimulants.”

“Prescription stimulant use at Yale helps the school’s bottom line,” student Eric Stern wrote for the Yale Daily News Magazine. “It makes students look smarter and more accomplished and more able to accomplish everything with seeming ease and efficiency.”

And while some schools have prohibited on-campus doctors to prescribe Adderall or similar drugs, and others have required students to sign agreements not to sell or share their pills, Graham contends it’s really easy for students to get their hands on the drugs.

“Graham had prepared a spiel for his family physician, describing ADHD symptoms that he doesn’t have, but he needn’t have bothered,” according to the Morning Herald.

“’He asked me “do you have a hard time concentrating?” I said yes. And that was it. That was the end of the conversation.’ The doctor wrote him a script for 40mg of Adderall a day, renewable every three months.”