Clinical trials are a vital part of the medical research process: they are used to determine how, and if, a medication being tested works for the illness it is purported to treat, what the side effects are, what else it might do, what the appropriate dose is&mash;enough to have an effect, not enough to be dangerous&mash;and how effective it is compared to existing treatments for the condition, if any. Every day, people are being recruited to participate in these trials to help advance the cause of science. Far too often, however, an important element is missing. Until relatively recently, with few exceptions, trials are conducted only on men unless the medication is for a condition that only or primarily strikes women.
There are several reasons for this. One is a fear, occasionally justified, that female subjects’ menstrual cycles will have an unrecorded impact on the results. Another, seemingly contradictory, reason is an assumption that men and women are pretty much the same, except for the plumbing; often, this translates in practical terms into an assumption that women are men with different plumbing. Despite a law passed over 20 years ago mandating that women be included in clinical trials funded by the National Institutes of Health, most medications are tested primarily on men, not generally out of a desire to exclude women&mash;either from the trial or from the medication’s benefits&mash;but out of a belief, which may not even be recognized consciously enough to be considered a conviction, that it simply does not matter.
Except it turns out that it does. Male and female bodies have different levels of hormones, anatomical differences beyond the obvious ones, and other differences that could make a significant difference in how drugs affect the body. That’s why men and women tend to experience different levels of intoxication from the same amount of alcohol, even taking weight into account. It’s also why manufacturers of sleep aids containing zolpiem, the active ingredient in Ambien, had to change labeling last year to list two recommended doses. The single listed dose, still recommended for men, was twice the dose now given for women, who were reporting high rates of sleep driving and other dangerous reactions.