Per 2012 numbers from the CDC, an estimated 6.4 million people in the United States have attention deficit hyperactivity disorder, or ADHD. Within this statistic, about 3.5 million children are taking some sort of medication, including Adderall, for the condition. According to the New York Times, the legal sale of prescription stimulants soared to $9 billion in 2012, more than a four-fold increase in just a decade. ADHD is a big business and more pills are available to patients than ever.

Unfortunately, many of those pills end up in the hands of teenagers who aren’t suffering from ADHD. Adderall abuse, normally associated with college students, is becoming a bigger problem with teens who are misusing the drug in an attempt to help with studying or simply for a recreational high. And because Adderall is so commonly prescribed, many students have learned how to work the system to obtain a script from their doctors.

Adderall has been proven to help students with ADHD—teachers have seen these benefits with kids whom they know have the condition. In non-ADHD students, Adderall can result in dangerous side effects. The signs of abuse are there; here are some signs that teachers should be looking for:

Grades Start Faltering

In ADHD patients, Adderall can help improve grades—kids are less distracted during class and tests and focus more on the task at hand. For this reason, many non-ADHD teens turn to the drug in the hopes it will give them an edge when they study. However, research has shown that Adderall does not produce the same benefit and, in fact, may hurt grades. Kids who are misusing Adderall may take an increased dosage, but even at the right dosage, the drug is an amphetamine and is unpredictable for a user who doesn’t need it. If you see the grades of honor students—particularly the ones you know are driven to study—start dropping off, it might be a sign of Adderall abuse that is backfiring.

Inability to Concentrate

The mix of stimulant ingredients in Adderall gives kids with ADHD better concentration. Most teens don’t unusually struggle with concentration, so introducing a strong amphetamine into their system can leave them wired, jittery, and unable to focus during class. Again, if a previously attentive student is now seemingly always out in space (more so than any average teenager), something else might be at play—possibly Adderall abuse.

Fatigue

Fatigue is another tricky symptom to diagnose in teens because, after all, most kids this age don’t get enough sleep to begin with. Insomnia is a possible side effect with Adderall use, so how do you distinguish between a student who is misusing the drug and one who is simply staying up late? At the risk of being redundant, knowing your students is the best way to see the signs of abuse. Kids with ADHD who are fatigued might be grappling with Adderall side effects. Students without ADHD who are continually dozing—and doing so after being otherwise alert for weeks or months beforehand—could be misusing the drug.

Intensified Personality

Another indicator that a student might be abusing Adderall is a personality taken to another level. Unusual excitability, extreme talkativeness and aggression are some signs the drug is being misused.

Weight Loss

Because Adderall is an amphetamine, users may naturally be more active. Also, a side effect of abusing the drug is a loss of appetite. This double whammy can result in weight loss in otherwise healthy students.

Other Side Effects vs. Signs of Abuse

Like almost every drug, Adderall comes with side effects. And also like every drug, abusing Adderall can result more serious long-term effects. Here is a comparison of side effects, including some already discussed, that are heightened when Adderall is abused:

Besides looking for these signs of Adderall abuse, teachers can take an additional step toward preventing teens from abusing the drug, particularly for study purposes: Reminding them that no grade is worth their health.

How much of a problem is Adderall abuse at your school?