Until I spoke to a recent graduate of a prestigious law school, I didn't realize students use Adderall to enhance their studying and test-taking. I don't think some of them are aware of the drug's downsides.

Adderall is normally prescribed for attention deficit hyperactivity disorder (ADHD) to boost dopamine in the brain. But in people without ADHD, it can enhance mental performance and lower fatigue. On it, students feel more alert, focused and think quicker.

In recent years Adderall has become the drug of choice for overachievers and dubbed a cognitive steroid. One study reported that 20% of college students have taken Adderall or a related drug, Ritalin.

Some students are crushing and snorting it to gain instantaneous focus, without realizing they are becoming addicted. If taken regularly for more than a few weeks, or in high doses, stopping the drugs will cause withdrawal reactions. The symptoms include anxiety, depression, hypersomnia or insomnia, paranoia, hyperactivity, irritability, or personality changes, and in severe cases, psychosis.

We're also learning from surveys that most college students who abuse Adderall also abuse alcohol and are three times more likely to use marijuana, five times more likely to take pain relievers, and eight times more likely to use cocaine. You may be shocked to learn ADHD prescription drugs are class 2 controlled substances grouped with highly addictive drugs such as cocaine. They are illegal to possess without a prescription in most states.

Despite the downsides of neuroenhancers, they may have a place in improving human health. As the population ages, cognitive enhancers can improve quality of life and compensate for mental decline. But the long-term effects of these drugs are still unknown, and need to be studied so that individuals can make responsible decisions about their use.