With midterms coming up at many college campuses, some students will be turning to a study aid that can't be checked out of the library.

They're called "smart drugs," prescription stimulants intended for people who suffer from attention-deficit hyperactivity disorder but used by millions of young people in search of increased focus and stamina.

A group of students from Boston University spoke to NBC News about the growing problem of "academic doping" for TODAY's series "Campus Undercovered."

"The majority of people that I know are taking it," a student named Gabi said.

Another, named Wyatt, said everyone in his social circle uses drugs like Adderall, Ritalin, Focalin, Vyvanse. "Every single person," he said. "You can go up to the second floor of the library and see, you know, a full wing of people just cracked out."

One study estimated that a third of college students may be misusing ADHD stimulants — troubling experts who say the pills can lead to addiction, psychiatric breakdowns and even suicide.

Watch our "Campus Undercovered" report for more on the dark side of "academic doping."