Relievers Work Differently
in Men and Women
Research suggests that men and women use separate mechanisms
in the brain to achieve pain relief.
More than 50 million Americans live with chronic pain, while millions
more suffer bouts with acute pain due to injuries or surgery.
And while both men and women endure this affliction, pain is
not always an equal opportunity burden: women are more apt than
men to suffer from chronic pain and experience more severe and
longer lasting pain.
Moreover, research shows that men and women also respond differently
to pain medications and an increasing number of studies suggest
that the fundamental biology of pain and pain relief differs between
In fact, accumulating evidence implies that the days of sex-specific
pain killers perhaps pink and blue pills may not
be too far off.
The first hint that pain medication might work differently in
men and women came as a surprise to researchers at the University
of California at San Francisco (UCSF). They gave morphine-like
painkillers called "kappa opioids" to patients who had undergone
surgery to remove their wisdom teeth.
The drugs gave more powerful and long-lasting pain relief to
women compared with men. In addition, at some doses, kappa-opioids
were exceptionally good pain relievers in women and actually made
the pain worse for men. Understanding the cause of this discrepancy
will lead to better pain relief for both sexes.
Sex-specific pain relief is not just a phenomenon confined to
opioids. Recent research shows that ibuprofen, the active ingredient
in a number of over-the-counter medicines, may be much less effective
in women than men.
Researchers at the University of New South Wales in Australia
randomly gave a small group of men and women either ibuprofen
or a sugar pill and then used electricity to cause experimental
pain. They discovered that ibuprofen gave significant pain relief
only in men.
New Research Implicates Genetics
New research by Jeffrey S. Mogil, professor of psychology at
McGill University in Montreal, Canada, suggests that men and women
use separate mechanisms in the brain to achieve pain relief.
By studying genetically modified mice, Mogil and colleagues
have discovered that kappa-opioids, the same pain relievers UCSF
researchers found were more effective in women, work through different
pathways in female and male mice.
These scientists have identified the exact gene that controls
for this sex difference in mice and are currently working on identifying
the human gene equivalent.
Mogil's research suggests that men and women are wired differently
for pain relief. Finding the genetic cause for this difference
may lead to the development of a completely new class of pain
These hypothetical drugs would be the first example of a medication
unrelated to reproduction that works in exclusively in one sex.
Why Do Pain Medications Work Differently
in Men and Women?
While Mogil's research implicates differences in brain biochemistry,
the question of why pain killers work differently in men and women
is far from answered. Hormones, anatomy and sociocultural factors
may also play a role.
Research suggests that a woman's sensitivity to pain changes
throughout the menstrual cycle due to fluctuating levels of the
hormones estrogen and progesterone. Other studies indicate that
women's freedom with expressing pain may boost the perceived effectiveness
of pain relievers.
What's more, women are more apt to be dependent on so-called
"polytherapy" to alleviate pain. For example, women often combine
prescription medications with relaxation techniques such as yoga
and psychotherapy to help them manage pain.
Thus, biological differences may interact with social and cultural
issues to produce the observed sex differences in pain relief.
Only further research examining the underlying cause of these
sex differences will sort out the relative impact of each one
of these factors.
Both men and women can use the following tips
from the American Pain Foundation to help take control of their
Phyllis Greenberger, MSW, is president & CEO of the Society
for Women's Health Research
- Keep a pain diary. Record the time, type and intensity of
the pain on a daily basis or even from episode to episode.
Note what you were doing when and immediately before the pain
began or changed. Explain how the pain feels: sharp, dull,
throbbing or tingling? Record the intensity of the pain on
a scale from 1 to 10. These details may help you doctor find
the cause and best treatment for the pain.
- Discuss all medications including over-the-counter, alternative,
and dietary supplements with your doctor. Talk to your doctor
before using any type, even "all-natural", pain relief. Combining
non-prescription pain relievers including aspirin, acetaminophen,
and non-steroidal anti-inflammatory drugs can increase the
risk of stomach ulcers. "All-natural" doesn't mean safe. The
U.S. Food and Drug Administration (FDA) does not regulate
food supplements leading to unreliable and inconsistent product
quality and dose. Complementary medicines can also interact
with traditional medications and cause life-threatening results.
- Try Non-Drug Pain Relief. Relaxation techniques such as
yoga and meditation, biofeedback, and hypnosis have been shown
to help relieve chronic pain.
- Get Moving! You don't have to be a marathon runner to reap
the benefits of exercise. Walking, stretching, and simple
activities like raking leaves, gardening and mowing the lawn
all promote mental and physical health.
- Join a support group. Talk therapy has been shown to help
people manage their pain. Ask your doctor, look in newspapers,
phone books or on the Internet for names of groups in your
Reference Source 104