New research is finding that many doctors and physicians are prescribing the use of anti-depressant drugs for a number of conditions that are not related to depression, according to CBS News.

Jenna Wong, M.Sc., of McGill University in Montreal, and lead author on the new study, said the researchers suspected the drugs could be being used for non-depression related treatments, but they were unable to find a lot of previous research on the topic.

“We wanted to see exactly why antidepressants were being prescribed, how often, and for what indications,” commented Wong.

To undertake the study, the research team examined over 100,000 prescriptions written by around 160 primary care physicians and covering almost 20,000 patients under their care.  The physicians in the study, from Quebec, provided documentation for the medications they had provided their patients, and at least one reason for prescribing the particular drug.

All anti-depressants were included in the study, with the exception of an older drug, monoamine oxidase, that is prescribed so infrequently it would not be useful to track for the analysis.  The focus was on the period between January 2006 and September of 2015.

Surprisingly, the findings revealed that only 55 percent of the primary reasons anti-depressant drugs were given to patients was for the treatment of depression itself.  The remaining 45 percent were used to treat a number of other conditions, including anxiety disorders, insomnia, pain, and panic disorders.

One of the most alarming revelations was the fact the almost two-thirds of these anti-depressants given for reasons other than depression, were considered “off label.”  That means the drugs themselves were not approved by regulatory agencies to treat the conditions for which they were prescribed.

In addition, the physicians involved in the study also prescribed anti-depressants for the treatment of such illnesses as migraine, attention-deficit/hyperactivity disorder (ADHD), and disorders of the digestive system.

Wong said this was an area of concern for the researchers, since many of the off-label uses of the drugs may not have been backed up by documented scientific evidence of their impact on the patients.

Wong added she could not make a judgement on whether or not the drugs worked for those to whom they were prescribed, but without scientific investigations and evidence, the patients could have been exposed to the risk of adverse health effects.  There is also the possibility the drugs had no effect at all and were taken unnecessarily.

But, Dr. Norman Sussman, psychiatrist and Director of the Treatment Resistant Depression Program at NYU Langone Medical Center, said he didn’t think the findings from this new study were anything to worry about.  He points out that medical textbooks from as far back as 50 years ago were recommending these drugs for treatment of conditions such as pain management and insomnia.

“For insomnia use, most knowledgeable internists prescribe many of these medications because they are more effective and less problematic than drugs indicated for insomnia, such as Lunesta and Sonesta, which can have addiction counter-indications,” commented Sussman.

He added the findings validate the fact that primary care physicians are knowledgeable about using these types of drugs to treat a variety of conditions and illnesses.  He felt the results demonstrated “a certain sophistication on the part of practitioners to use these drugs off-label.”

Wong admits that physicians could be discussing with their colleagues what medications work well for certain conditions, and at least have anecdotal evidence to validate their use.  She said it was more than just word of mouth, and added marketing and promotions from pharmaceutical companies could also be playing a role in the decision to use the anti-depressants.

In an article on pharmacytimes.com, Wong offered that drug formulary lists may also be influencing a doctor when determining which drug to use.  “The costs associated with prescribing a drug that doesn’t appear on a formulary may be prohibitive for some patients,” explained Wong.  “Physicians might refrain from prescribing the most appropriate drug if it means savings for the patient, although it’s unclear how many times that decision is actually communicated to the patient.”

Although the research was done in Canada, experts say they would expect the same or very similar results if a comparable study was completed on patients in the United States.

Findings from the new research were published in the Journal of the American Medical Association.