Men, Women and Pain
Differences in how the sexes deal with - and find relief from - pain
By Denise Lynn Mann
If you're a woman and think some pain medications don't make you feel much better, you may be right. Men and women respond to pain in different ways, both physiologically and emotionally.
Physical Differences
There are pharmacokinetic concerns - that is, differences in the ways male and female bodies absorb, store, break down and excrete drugs," says Marianne Legato, MD, founder and director of the Partnership for Gender-Specific Medicine at Columbia University in New York City. As a result, there are differences in how drugs physiologically affect men and women.
The pharmacokinetic differences appear in about only 20 percent of drugs, according to a study of 300 drugs submitted to the FDA between 1994 and 1999. The popular dietary supplement St. John's wort, commonly used for the mild-to-moderate depression or pain and inflammation associated with arthritis-related conditions, is a prime example.
St. John's wort increases the effects of a hormone (called cytochrome CYP3A), which is produced more abundantly in women than in men. The increased hormone causes women's bodies break down the herb so fast that it laves the body before it provides any relief. Cytochrome CYP3A has the same effect on some prescription and over-the-counter medications.
Another example: Regular use of aspirin reduces the risk of heart attacks in men, but instead reduces the risk of strokes in women, according to a research team from the State University of New York in Stony Brook.
Knowing these differences helps doctors and patients better understand why a treatment may or may not be working and how to adjust it. The FDA has proposed that prescription drug labels highlight, along with serious and common side effects, any differences between the way the drug acted in women and men in clinical trials.
The information isn't coming quickly enough, says Sherry Marts, PhD, the vice president of scientific affairs at the Society for Women's Health Research in Washington, D.C. The Society is a non-profit organization focusing on advancing women's health with gender-specific research, education and advocacy.
"We haven't been seeing anything definitive on labels," she says. "Occasionally labels will say, 'no sex differences apparent from clinical trials' or that a difference in metabolism was found, but it was not clinically significant." Ideally the Society would like companies to ask three separate questions when doing research on new drugs:
(1) Is it safe and does it work in men?
(2) Is it safe and does it work in women?
(3) Does it work differently in men and women, and what significance does that have?
More than health care will be affected by these answers, adds Marts. "Ultimately this type of information will be of value to researchers, advancing knowledge that could bring us to a better understanding of the mechanisms more quickly," she says.
