SATURDAY, Aug. 31, 2002 (HealthDayNews) -- Do drugs discriminate by gender?
Absolutely, say doctors and scientists -- certain drugs can trigger side effects that trouble women more than men. Conversely, other drugs can shortchange men, not giving them, for instance, the pain relief that women get from the same medications.
But that doesn't mean these drugs can't benefit both.
"It's certainly a cause for concern -- men and women do respond differently to certain drugs. And it's really crucial to look for these differences in clinical trials and post-trial use," says Sherry Marts, scientific director for the Society for Women's Health Research, which compiles information on drugs and their effects on the different genders.
"But," she adds, "it hasn't resulted in a lot of serious health problems. And if they [drug makers] figure out what's going on, they can reverse the effects."
One of the more significant problems facing women: There are approximately 50 drugs that have been shown to increase the risk for an irregular and rapid heartbeat, a condition called Torsades de Pointes.
When women take one of these drugs -- including a number that, ironically, are designed to treat irregular heartbeats -- they're automatically at higher risk for Torsades de Pointes than men, health experts say.
"This is serious in the sense that every drug class has a drug within it that has this problem. And more importantly, even though women are now being included in study data for drugs, the data isn't being analyzed by gender," says Dr. Raymond Woosley, vice-president of health sciences at the University of Arizona and the author of studies on drugs' effects by gender.
Drugs prescribed to treat irregular heartbeats that can lead to Torsades de Pointes include brand names like Cardioquin, Quinaglute, Corvert and Norpace. In addition, some anti-depressants, like Zoloft and Prozac, and even common antiobiotics like erythromycin -- when given intravenously -- carry warnings of an increased risk of Torsades de Pointes, Woosley says.
More drug manufacturers are noting the risk to women on the drugs' packaging.
Sotalol, for instance, which goes by the brand name Betapace AF, is another drug used to treat irregular heart beats.
Clinical trials before its approval by federal regulators showed that approximately six percent of the 3,135 men and women who took the drug suffered irregular heartbeats as a side effect. Of the six percent, however, two-thirds were women, a "statistically significant number," says Dr. John Williams, director of clinical research in the cardiovascular division of Berlex Laboratories, which manufactures the drug.
"This is a common side effect of all this class of drugs," Williams says, and women have an increased susceptibility to it. For that reason, the potential side effect for women is mentioned in the consumer information packet that accompanies the drug.
But the risk of side effects like Torsades de Pointes shouldn't preclude women from the benefits of an effective drug, says cardiologist Neica Goldberg, chief of the women's heart program at New York City's Lenox Hill Hospital.
Most of these drugs are first prescribed in a hospital where the physician can monitor their effects, she says. "And any physician prescribing them knows it is a known side effect that many anti-arrhythmic drugs actually increase the risk of Torsades de Pointes."
"There may be some predisposition for women for this, but that should not mean women should not have the drug. Doctors should be more cautious in the dosages, and to know that the dosage has to be adjusted downward," she adds.
Men aren't impervious to the drug-gender pitfall. For example, it's been found that men are far less likely to experience pain relief than women when given a prescription for the standard painkiller nalbuphine (brand name Nubain) after surgery.
"We were amazed and then perplexed, because this drug has been around for a long time," says Dr. Jon Levine, a professor of medicine at the University of California, San Francisco, who conducted a study of the effectiveness of nalbuphine on the pain resulting from removal of impacted wisdom teeth.
"The women could get a very powerful, long-lasting analgesic effect that was better than morphine. But for men, the response was weak, and in some doses, it made the pain significantly worse," he says.
It's still not known why these gender differences exist, Levine adds. "We have to begin to tease out how the nervous system in men and women is different," he says.
There's a growing body of literature on the topic, and physicians, other health-care professionals and the public should be alert to the new information, he says.
"For individuals as well as health-care providers, if you don't get the response you expect from a drug, you have to be open-minded to the fact that gender may actually be important," Levine says.
Marts advises everyone to ask their doctors about possible gender effects of drugs they're prescribing. "It doesn't hurt to ask the question," she says.
Also, people should be sure to tell their doctor what other medications they're taking, not just prescribed drugs but over-the-counter drugs and herbal remedies, she adds.
"This applies particularly to women, because women take more drugs in combination because of birth control pills," Marts says.
What To Do
For a list of drugs that have been shown to lead to Torsades de Pointes, visit the University of Arizona. For advice on how to safely use medications, see the Public Citizen's Health Research Group.
