Think antidepressants are only used to treat severe depression? Think again. According to a report from the Los Angeles Times, a recent study has found that doctors are prescribing more and more antidepressants to treat symptoms that may be only mildly related to depression.

The study was published in the Journal of the American Medical Association on Tuesday, and showed that nearly three in 10 antidepressant prescriptions issued between the years of 2006 and 2015 by doctors in Canada were intended to treat conditions for which the medications had not received approval from the U.S. Food and Drug Administration.

Among the ailments treated by antidepressants were insomnia and pain. The study also showed that antidepressant prescriptions were written to treat migraines, menopausal symptoms including hot flashes, attention deficit and hyperactivity disorder, and even a number of digestive illnesses. Doctors also prescribed antidepressants to treat anxiety disorders and panic attacks.

Altogether, nearly 45 percent of antidepressant prescriptions written during the study period were intended to treat something other than depression. A number of these ailments were considered variants of depression, and a number of medications used to treat depression were also shown to be effective at treating these conditions as well.

The study found that the number of antidepressant prescriptions written to specifically treat depression continued to fall throughout the 2006-2015 period. According to a statement from the authors, “The mere presence of an antidepressant prescription is a poor proxy for depression treatment.”

The findings suggest the necessity for a serious overhaul in antidepressant research. While this class of drugs has long been used to treat depression, using them for non-approved purposes could have unintended consequences.

The study builds on the findings of previous research that showed physicians were prescribing antidepressants without any specific diagnosis at all. A 2011 study found that nearly 56 percent of antidepressant prescriptions written from 1995 to 2007 were issued without a formal depression or anxiety disorder diagnosis.

A press release from McGill University describing the details of the study can be found here.