For a moment, forget the skyrocketing addiction rates that can lead directly to harder drug use. Ignore the political might of a quarter-billion-dollar annual lobbying effort, by far the most robust in our heavily financed—and legislatively influential—political system. Disregard the number of physicians who think nothing of jotting down yet another prescription for opioid painkillers and the patients who eagerly fill them.

Now comes the news that these drugs might not even work. A study released this week by the school of psychology and neuroscience at University of Colorado Boulder suggests that even brief opioid use may actually increase chronic pain.

The three-month study showed that lab rats reacted to a five-day dose of morphine by developing symptoms of long-term chronic pain after receiving the treatment. This means that the drugs we’re leaning on so heavily after an injury, surgeries, or procedures such as root canal may actually be making our recovery worse—while also sending some of us down a path toward addiction.

The reason for this appears to be that such treatment, even if it’s brief, floods nerve cells in the spinal cord with intensified pain signals, which prolongs discomfort rather than alleviating it.

Although these results are preliminary, they demonstrate how we’re only beginning to understand yet another risk factor that could make opioids more dangerous than we already knew—and maybe pointless to begin with.

The study also underlines the need for more research into safe and effective pain treatments, and part of this effort needs to include medical marijuana. Now that federal restrictions on such research are beginning to loosen, the sooner we can wean Americans off of pernicious substances like opioids, the healthier we’ll be.