New research published in the journal JAMA Internal Medicine suggests that doctors shouldn’t begin prescribing antidepressants for young adults and teens with high doses, as it will increase their risk of suicidal behavior. The new study found that younger patients who started their treatment with larger-than-recommended dosages of antidepressants were more than two times as likely to self-harm as those who started with treatment with the recommended level of doses.

“One can quibble about how much benefit there is at typical doses, and my sense is that the benefit is modest at best,” said associate director of the Injury Control Research Center at the Harvard School of Public Health in Boston Dr. Matthew Miller, who also authored the study. “But there’s no evidence that higher initial doses are going to help more than lower doses.”

In fact, he says, higher doses could only increase risk.

The new research is likely to play a dramatic role in the ongoing debate over whether or not it’s actually safe for doctors to prescribe young adults and children with antidepressants. For years the Food and Drug Administration has required antidepressants to have warning labels that the medicine could increase the risk of suicidal behavior and thinking in people under the age of 25.

In 2007, the Journal of the American Medical Association published a review that concluded the benefits of prescribing young adults with antidepressants outweighed the potential harms. Another study from 2007 published in the American Journal of Psychiatry showed that despite a decrease in the prescribing of antidepressants to teens and young adults, youth suicides increased. Critics cited the warning labels, which deterred children and young adults from taking the medicine, for the increase in suicides.

However, up until now there’s been no study that looks at the risk of suicidal thoughts and behavior by drug dosage, as this latest study has. It found that for those who took the recommended dosage, the risk was 1.4% while higher doses had a risk of 3.1%.

Child psychiatrist R. Scott Benson says that some children and teens are prescribed antidepressants “in too casual a way.” He went on to say that “We have to make sure their level of depression is serious enough to warrant treatment with an antidepressant.”

Miller said, “If I were a parent, I definitely wouldn’t want my child to start on a higher dose of these drugs.”