It is now widely believed that pain affects men and women differently. While
the sex hormones estrogen and testosterone certainly play a role in this
phenomenon, psychology and culture, too, may account at least in part for
differences in how men and women receive pain signals. For example, young
children may learn to respond to pain based on how they are treated when they
experience pain. Some children may be cuddled and comforted, while others may
be encouraged to tough it out and to dismiss their pain.
Many investigators are turning their attention to the study of gender
differences and pain. Women, many experts now agree, recover more quickly from
pain, seek help more quickly for their pain, and are less likely to allow pain
to control their lives. They also are more likely to marshal a variety of
resources-coping skills, support, and distraction-with which to deal with their
Research in this area is yielding fascinating results. For example, male
experimental animals injected with estrogen, a female sex hormone, appear to
have a lower tolerance for pain-that is, the addition of estrogen appears to
lower the pain threshold. Similarly, the presence of testosterone, a male
hormone, appears to elevate tolerance for pain in female mice: the animals are
simply able to withstand pain better. Female mice deprived of estrogen during
experiments react to stress similarly to male animals. Estrogen, therefore, may
act as a sort of pain switch, turning on the ability to recognize pain.
Investigators know that males and females both have strong natural
pain-killing systems, but these systems operate differently. For example, a
class of painkillers called kappa-opioids is named after one of several opioid
receptors to which they bind, the kappa-opioid receptor, and they include the
compounds nalbuphine (Nubain®) and butorphanol (Stadol®).
Research suggests that kappa-opioids provide better pain relief in women.
Though not prescribed widely, kappa-opioids are currently used for relief of
labor pain and in general work best for short-term pain. Investigators are not
certain why kappa-opioids work better in women than men. Is it because a
woman's estrogen makes them work, or because a man's testosterone prevents them
from working? Or is there another explanation, such as differences between men
and women in their perception of pain? Continued research may result in a
better understanding of how pain affects women differently from men, enabling
new and better pain medications to be designed with gender in mind.
The bladder is the hollow organ in the lower abdomen that stores urine. As the bladder fills, muscles in its walls relax so that it can expand. As the bladder empties during urination, the muscles contract to squeeze the urine out through the urethra.
Several different bladder problems can cause pain. The three most common causes of bladder pain are interstitial cystitis, urinary tract infection, and bladder cancer.
Pain in Aging and Pediatric
Populations: Special Needs and Concerns
Pain is the number one complaint of older Americans, and one in five older
Americans takes a painkiller regularly. In 1998, the American Geriatrics
Society (AGS) issued guidelines* for the
management of pain in older people. The AGS panel addressed the incorporation
of several non-drug approaches in patients' treatment plans, including
exercise. AGS panel members recommend that, whenever possible, patients use
alternatives to aspirin, ibuprofen, and other NSAIDs because of the drugs' side
effects, including stomach irritation and gastrointestinal bleeding. For older
adults, acetaminophen is the first-line treatment for mild-to-moderate pain,
according to the guidelines. More serious chronic pain conditions may require
opioid drugs (narcotics), including codeine or morphine, for relief of
Pain in younger patients also requires special attention, particularly
because young children are not always able to describe the degree of pain they
are experiencing. Although treating pain in pediatric patients poses a special
challenge to physicians and parents alike, pediatric patients should never be
undertreated. Recently, special tools for measuring pain in children have been
developed that, when combined with cues used by parents, help physicians select
the most effective treatments.
Nonsteroidal agents, and especially acetaminophen, are most often prescribed
for control of pain in children. In the case of severe pain or pain following
surgery, acetaminophen may be combined with codeine.
* Journal of the American
Geriatrics Society (1998; 46:635-651).
WebMD Public Information from the U.S. National Institutes of Health