Women are overmedicated because drug trials have focused on men, study finds
A recent study shows that women have nearly double the risk of experiencing adverse side effects from medications than men such as nausea, seizures and cardiac anomalies.
Data from thousands of existing studies revealed that although women were given the same amount of drugs as men, they had higher concentrations of the medications in their blood. It also took their bodies longer to eliminate them, leading to the harmful side effects documented in research past.
The issue is the product of biased clinical trials that have historically focused on men to test drug dosages, often leading healthcare professionals to overmedicate women, according to the paper published in June in the journal Biology of Sex Differences.
Because women are taking drugs tested long before they were included in clinical studies, the researchers recommend dosage reductions to prevent and limit unnecessary side effects.
“When it comes to prescribing drugs, a one-size-fits-all approach, based on male-dominated clinical trials, is not working, and women are getting the short end of the stick,” study lead author Dr. Irving Zucker, a professor emeritus of psychology and of integrative biology at University of California, Berkeley, said in a news release published last week.
“Neglect of females is widespread, even in cell and animal studies where the subjects have been predominantly male.”
It wasn’t until 1993 when the National Institutes of Health made the enrollment of women in clinical research funded by the NIH a law. The longtime exclusion was “based, in part, on unfounded concerns that female hormone fluctuations render women difficult to study,” Zucker said.
That same thinking went for women of childbearing age, the researchers said. Medical and liability issues concerning potential harm to fetuses and pregnant women naturally deemed men the simpler, safer test subject.
The researchers analyzed data from over 5,000 published studies and found drug dose gender gaps for 86 different medications approved by the U.S. Food and Drug Administration, “including antidepressants, cardiovascular and anti-seizure drugs” and pain killers.
In more than 90% of cases, women suffered from nausea, headaches, depression, cognitive deficits, seizures, hallucinations, agitation and cardiac abnormalities about twice as often as men, according to the study.
However, the researchers note that it cannot be proven that a specific drug caused the adverse side effect, “rather than an underlying illness or other concomitant medication.”
Why do women react to medications differently than men?
For starters, women are more likely than men to use two or more medications at the same time, according to the researchers, which could explain why females see more adverse side effects from drugs than men.
Women also tend to have a lower body weight average and organ size than men, as well as a higher percentage of body fat, “which affects the absorption and distribution of drugs.”
Reproductive hormones play a role in the metabolization of drugs, too, Dr. Lee Cohen, head of the Center for Women’s Mental Health at Massachusetts General Hospital in Boston, told WebMD; Hormones control how much time the medicine spends in the gut and the processes that break them down.
Drugs also work differently in post and premenopausal women depending on hormone and blood levels. But experts say the problem is that studies aren’t designed to look specifically at sex and gender differences when analyzing proper drug dosages.
“Regulatory agencies have historically paid insufficient attention to differences between women and men in terms of both sex and gender. In addition, this disparity allows for misleading drug marketing,” the researchers wrote in the study. “We… recommend that sex-based dosing recommendations be disseminated to physicians and appear on drug labels.”
