A new study suggests that more college students are using a stimulant commonly prescribed for attention-deficit hyperactivity disorder (ADHD) as a study aid, Philly reports.  

"The majority of adults who are using Adderall nonmedically are in the age range of 18 to 25," said lead researcher Dr. Ramin Mojtabai, a professor of mental health at Johns Hopkins Bloomberg School of Public Health in Baltimore.

The study found that most of the students get the pills from friends or relatives who have prescriptions.

Mojtabai and his team said that they suspected that college students use Adderall, a stimulant, to stay up all night to study for exams. In the same way, young working adults might use it to stay sharp and focused on the job.

Also, "it's possible some of this use is recreational," said Mojtabai.

"There's a pattern of concomitant use of other substances in about half of these adults."

The researchers found that the misuse of the drug among U.S. adults jumped 67 percent from the year 2011 and related visits to emergency rooms went up by 156 percent.

According to the U.S. Food and Drug Administration, the use of amphetamines, including Adderall, can lead to dependence, sudden death and serious cardiovascular events,

"They are not harmless simply because they are prescribed by doctors," said study co-author Dr. Lian-Yu Chen, an attending psychiatrist at Taipei City Psychiatric Center in Taiwan.

The study was published Feb. 16 in the Journal of Clinical Psychiatry.

The researchers said that the preference of college students for Adderall over the other stimulants might be because it increases two brain chemicals linked with better cognitive functioning and also have a reputation for making people smarter.

Dr. Robert Glatter, an emergency physician at Lenox Hill Hospital in New York City saids,

"This study highlights the growing problem of drug diversion as the main factor behind both misuse and increased emergency department visits for Adderall," said Glatter.