The improper use of ADHD medications in children is on the rise, according to a new study published in the journal Pediatrics.

According to the findings, there was a 64 percent increase in calls to poison control centers between 2000 and 2014 related to the meds.

The study also found that prescriptions for ADHD meds have more than doubled since 2005. But 82 percent of the more than 150,000 poison control calls were considered unintentional exposures. The study also identified three fatal incidents, all involving teenagers.

"These are potentially very dangerous drugs," says Dr. John Zaso, who is a pediatrician.

Zaso says some of the incidents can stem from people using a family member's properly prescribed drugs or from kids accidentally getting into the bottles.

Symptoms of misuse can include elevated blood pressure, heart arrhythmia and the risk of stroke, Zaso says.

Experts say parents should keep close track of any prescription medications they keep in their homes.