Lies They Tell Us…Morphine May Make Pain Last Longer

Morphine is probably everyone’s first thought when they suffer an injury that causes serious pain. After all, what is better than morphine when you are in agony? Depending on how similar humans are to rats when it comes to nerve pain, morphine may actually make the pain last longer.

This could present a terrible choice for people who are in pain. Imagine your doctor asking, “Do you want to feel better now and be in pain longer, or suffer now and have the pain go away sooner?”

Morphine Or Saline For Sciatica?

Researchers recently induced a nerve injury in a group of male rats to see how they responded to morphine. Ten days after surgically pinching their sciatic nerves, the researchers gave half of the rats a five-day course of morphine while the other half were given saline. (Anyone who has ever experienced sciatic nerve pain is at this point imagining how they would be begging for the morphine…)

The interesting result of this study is that rats that received saline actually recovered faster than the rats that were mercifully given morphine. Their recovery was tested by poking the rats to see how sensitive they were to the injury. The rats that did not receive morphine recovered from the nerve injury in four weeks, but the rats that did receive morphine took eight weeks to recover.

Say What?

It seems counter intuitive that pain management would extend the pain after an injury. After all, being able to comfortably rest is supposed to promote healing.

The researchers in this study found that the rats that received morphine also experienced inflammation in their spinal cords. The theory is that the morphine was treated as a threat by the immune system. In response to this perceived threat, the rats’ immune system triggered the spinal swelling through the use of special cells known as microglia.

Rats And People

There are still a lot of questions about the impact of morphine on pain that were not answered by this research study. For one thing, nobody knows if humans actually have the same response to morphine as rats. (Does anyone want to volunteer to have their sciatic nerve pinched?) Another question is whether or not all opioid-based pain medicine would have the same response as the morphine. Drugs like Vicodin and OxyContin are also opioid-based, but were not included in the study.

Another complication of applying this research to people is that the rats were all genetically similar. People, on the other hand, are a lot more diverse than the rats that were subjected to this research. Since people tend to have differing responses to pain and opioid pain medicine, the response between people could vary if humans do respond the same way as rats to morphine.


What would you do if you had to decide between short-term pain relief and a faster recovery?




Robert Witham
Robert Witham
A freelance writer and journalist, I am also a wandering minimalist. I never sit still for too long in one place. When I am not writing I can be found reading, enjoying a good cup of coffee, hiking, fishing, installing a new OS on my laptop, or building a website.