Ketamine is increasingly becoming popular as a treatment for depression, but a new study has found that the drug acts as an opioid and carries some serious risks.

Scientists have warned patients dealing with mental health issues against the use of the known party drug until more research has been done on the risk of tolerance, abuse, and dependence.

Ketamine As Antidepressant

Ketamine is widely used as an anesthetic approved by the World Health Organization as an "essential medicine." However, by night, it takes a new form: it is also known as a party drug that sends users into a disassociative state.

In recent years, it has also taken the role of an antidepressant for people who have not responded to ordinary treatments. It has not been approved by the Food and Drug Administration as a treatment for severe depression, but some doctors use it as an "off-label" antidepressant.

Some scientists even hailed it as an "exciting breakthrough in the field of depression research" and pharmaceutical companies are already using it as an inspiration for new prescription drugs for depression.

Ketamine As Opioid

However, the new study published in the American Journal of Psychiatry revealed that the antidepressant effects of ketamine require the activation of the opioid system in the patient's brain.

Scientists studied adults who have depression but have not responded to any regular treatments. They were given two doses of ketamine, each administered at least two weeks apart since the drug's antidepressant effects wear off until about a week.

An hour before the first dose, participants were given placebos. Meanwhile, an hour before the second dose, patients were handed the drug naltrexone, which blocks the effects of opioids.

Patients who received naltrexone said that they did not experience any improvement on pain and other symptoms of their depressions. In comparison, when they were handed placebo, they reported that their symptoms were alleviated. Naltrexone has not prevented the disassociation effect of ketamine.

More Research Necessary

Albeit the study is small, the finding might change the way ketamine is used as an antidepressant. However, authors of the paper clarified that they do not object to occasional ketamine use.

Dr. Alan F. Schatzberg, a co-author of the study, mentions that opioid painkillers are also okay use in emergency situations, but it poses the risk of dependence when taken regularly.

"More studies need to be done to fully understand ketamine before it's widely rolled out for long-term chronic use," he added.