New research has discovered the difference and the answer sits in the brain.
Women have to endure period pain and suffer through the trials of giving birth. Curiously though, they also often require twice as much morphine as men do, to produce the same amount of pain relief.
Why? A sexist answer might state that women are simply not as strong at facing pain as men are, but researchers from Georgia State University say there is another reason for the difference. It lies in something called our brain microglia.
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In a healthy individual, microglia travel around the brain looking for signs of infection.
Microglia are an important part of our system and are involved in the body’s response to pain medication like morphine. And it turns out, they are the target.
In the study, researchers gave male and female rats a drug that inhibits the activation of microglia in the brain. Once they did, they found the results to be curious.
When the activation of microglia was stopped in female rats, they responded much better to morphine given for pain. Before blocking the microglia, the females needed more morphine than the male rats, to feel pain relief.
Things improved so much for the female rats though once their microglia was blocked that their response to the pain relief medication then matched that of the male rats.
What does this mean for humans? Pain relief in women may have a new target.
“The results of the study have important implications for the treatment of pain,” said Dr. Anne Murphy, co-author on the study and associate professor in the Neuroscience Institute at Georgia State.
“(They) suggest that microglia may be an important drug target to improve opioid pain relief in women.”
Which is good news for women. Females suffer from a higher incidence of chronic and inflammatory pain conditions such as fibromyalgia and osteoarthritis, than men, and relief is needed.