Researchers who analyzed U.S. prescription data noticed a troubling pattern of antipsychotics being prescribed to young children, particularly boys, without a diagnosis indicating they have a psychiatric disorder.

The researchers found that 60% of the children did not get a psychiatric diagnosis with their antipsychotics prescription. In the 40% who did, the most common diagnosis was attention deficit hyperactivity disorder, or ADHD. The FDA has not approved the use of antipsychotics for ADHD.

“What we see is patterns of use, particularly in boys, that suggest that antipsychotics are largely not being used for the disorders the Food and Drug Administration has approved them for,” Michael Schoenbaum of the National Institute for Mental Health, who worked on the study, told NBC News. “Rather, among boys, particularly teenage boys, uses are much more consistent with prescribing to manage behavioral problems.”

Antipsychotics, which are used to treat bipolar disorder and schizophrenia, have a calming effect on agitated patients. Schoenbaum said it “dampens down their emotion” and “flattens” their energy. Antipsychotics can have a damaging effect on young children, who are better off being treated for behavioral problems with psychotherapy, behavioral therapy, and stimulant drugs like Ritalin, the researchers say.

“Even people who need to take these medications, people with psychosis disorders, the patient experience of taking these medications can be most difficult,” said Schoenbaum. “They feel like different people.”

Additional side effects include severe weight gain, metabolic disorders like diabetes, and some can affect brain development.